U.S. government investigators are seeking information about Wang Qishan, the powerful official leading China’s anticorruption campaign, in connection with their probe of J.P. Morgan Chase & Co.’s hiring of relatives and associates of Chinese government officials.

The U.S. Securities and Exchange Commission issued a subpoena in late April to the bank requesting all of its communications related to 35 mostly high-ranking Chinese government officials. Mr. Wang’s name was first on the list in the subpoena, a copy of which was reviewed by The Wall Street Journal. Prosecutors at the U.S. Justice Department have also requested information about Mr. Wang, according to people familiar with the matter.

The request for information regarding some of China’s highest-ranking officials could strain U.S.-China relations. Previous U.S. requests have unearthed accounts of Chinese government officials lobbying J.P. Morgan to employ relatives and friends. According to people familiar with the probe, investigators have already focused on the bank’s employment of the son of China’s commerce minister, Gao Hucheng, who offered to help the bank if it let his son hold on to his job at J.P. Morgan, according to emails between J.P. Morgan bankers. Mr. Gao is also on the list.

Authorities are carrying out a criminal investigation into J.P. Morgan and other banks regarding a law that bans companies from bribing foreign government officials. Regulators aren’t investigating the Chinese officials themselves, and there is no evidence of wrongdoing by Mr. Wang, Mr. Gao or others on the list. Neither official responded to requests for comment.

Mr. Wang is leading the biggest anticorruption campaign in China in a generation, investigating Communist Party leaders including former security head Zhou Yongkang. His role as one of the seven members of the Politburo Standing Committee, the Communist Party’s top decision-making body, and as secretary of the Central Commission for Discipline Inspection, its anticorruption body, would make any suggestion of improper behavior politically sensitive.

Efforts by U.S. government agencies to find communications related to Mr. Wang, even in service of an investigation into a U.S. bank, could be viewed by the Chinese government as an unfriendly act and add to tensions in the bilateral relationship.

Mr. Wang’s name hasn’t been previously mentioned in media reports as part of the investigation into whether J.P. Morgan hired relatives of top Chinese government officials in an effort to win business for the bank. The subpoena is a request for potential evidence rather than evidence itself.

The list of Chinese government officials on the subpoena represents a broad spectrum of the country’s powerful government and corporate officials. Other officials on the list include Minister of Public Security Guo Shengkun, People’s Bank of China Vice GovernorPan Gongsheng, the chairman of state-owned grain trader Cofco Corp., “Frank” Ning Gaoning, and a senior executive at state-owned shipping giant Cosco Group, Sun Jiakang.The list also names officials of the State-owned Assets Supervision and Administration Commission, which manages China’s state-owned companies, and regulators for the insurance, banking and securities industries.

Some people named on the subpoena have already been publicly connected in media reports to the probe, including: Mr. Gao, the commerce minister; Fu Chengyu, retiring chairman of oil refiner Sinopec, who referred Mr. Gao’s son to J.P. Morgan, emails indicate, and Xiang Junbo, an insurance regulator who urged J.P. Morgan’s chief executive, James Dimon, to hire a young associate of his, according to people familiar with the matter.

The officials, none of whom are accused of any wrongdoing, didn’t respond to requests for comment. A spokesman for Sinopec previously said that Mr. Fu didn’t recognize Mr. Gao’s son’s name.

None of the Chinese officials connected in media reports to bank hires have faced censure in China, and it is unclear whether the Chinese government views the type of bank hiring under investigation in the U.S. to be a problem. In a meeting of the Commerce Ministry’s Communist Party Committee in late March, more than a month after The Wall Street Journal published a report on Mr. Gao’s son, Mr. Gao urged officials to “manage families and familial affection, resolutely oppose a sense of entitlement, and have strict standards toward spouses, children and employees,” according to a summary of the meeting posted to the Commerce Ministry’s website.

The probe has focused broadly on a period starting around 2006 and ending in 2013, when J.P. Morgan ended a program for referred hires that some at the bank called “Sons and Daughters.” Investigators are also looking into the China hiring practices of global banks besides J.P. Morgan.

Renowned in Chinese officialdom as a problem solver, Mr. Wang headed China Construction Bank in the 1990s then served as mayor of Beijing and organizer of the 2008 Olympics. As one of China’s four vice premiers from 2008 to 2013, Mr. Wang advised then-Premier Wen Jiabao on finance and the economy. Mr. Wang led the Chinese side of the U.S.-China Strategic and Economic Dialogue, high-level talks between senior officials in both countries.

Actions taken by U.S. and Chinese law enforcement have had an impact on diplomacy between the two countries in the past. Last year, China suspended cybersecurity discussions with the U.S. after the Justice Department charged five members of the People’s Liberation Army with hacking into computers to steal technology. A Chinese Ministry of Defense spokesman disputed the charges, which he said “severely damaged mutual trust” between the countries. Last week, the U.S. charged six Chinese citizens with stealing sensitive technology from U.S. companies. A Chinese university employing three of the accused expressed its “indignation and firm denial,” in response to the charges, state media reported.

The SEC document issued to J.P. Morgan, dated April 29th, is the latest in a string of subpoenas issued in connection with the investigation, which was disclosed by the bank in August 2013. The subpoena requested a response by May 15th, although extensions have been granted in the past, a person familiar with the investigation said. It wasn’t clear how J.P. Morgan, which has been cooperating in the investigation, has responded to the subpoena.

Early this year, Chinese officials suggested to U.S. counterparts that Mr. Wang might visit the U.S. in the next few months, but never formally proposed the idea and had dropped it by April without explaining why, according to people familiar with the matter.

A person familiar with the investigation said the SEC’s approach to collecting evidence was very broad and that the agency has been subpoenaing “everything under the sun” related to referred Chinese hires at J.P. Morgan. Despite this, any potential penalty in the case isn’t expected to be large compared with other fines levied on banks recently for financial improprieties, that person noted. “You wouldn’t care if it wasn’t J.P. [Morgan],” the person said.

Spokesmen for the SEC and the Justice Department declined to comment.

The SEC subpoena also requires J.P. Morgan to produce a list of any officials at six Chinese government agencies who asked the bank to hire job candidates, provide all communications between the officials and the bank and then give details of interactions between the official and the bank for a year after any such job request. The agencies flagged by the SEC are the State-owned Assets Supervision and Administration Commission, the China Insurance Regulatory Commission, the China Banking Regulatory Commission, the China Securities Regulatory Commission, the Ministry of Finance and the Ministry of Commerce. None of the agencies responded to requests for comment.

—Christopher M. Matthews and Emily Glazer contributed to this article.