South Korea's military rulers are maneuvering for long-range political control of the government by exposing corruption among their civilian rivals and preparing new benefits for the million government and Army employes.

Officials are hoping that a pay boost planned for government workers and soldiers will win support for the small group of generals running the country and prevent discontent about inflation from fueling further political dissent.

An unusual June 18 disclosure of massive fortunes earned by leading civilian politicians also appears designed to gather backing from average Koreans unhappy with the impact of petty corruption on their own lives.

The martial law command charged that nine former political officials under detention, including the head of the nation's principal political party, Kim Jong Pil, amassed $142,158,000 through the abuse of political power, violating laws on financial contributions, taxation, foreign exchange controls and overseas holdings. The nine were arrested May 17 in a general roundup at night of political dissidents and possible rivals of Lt. Gen. Chon Doo Hwan, now leading a small military group in effective control of the government.

The government announcement said the nine agreed to forsake any public office in the future and "voluntarily donate property to the state" to repay their debt to the government. The announcement said the government decided to "reserve criminal punishment." This was seen as a way of limiting further corruption and giving some justification for what has been the sudden end of civilian government here since the October assassination of president Park Chung Hee.

The nation's nominal civilian leader, President Choi Kyu Hah, promised in a June 12 speech that a new constitution would be put to a national referendum by October and elections for president and National Assembly would be held next year. The corruption charges against Kim and the others "removes a lot of people who would have been important in contesting those elections," said a politician here, "but people really did not like those people having too much money, living like kings."

The government, while keeping a tight lid on dissent since a series of student riots and a mass insurrection last month in the city of Kwangju, loosened the reins slightly this week by reopening 23 colleges and universities. These include graduate schools, nursing colleges and medical schools, which have lacked serious antigovernment student movements. Officials said more of the approximately 150 colleges still closed would be opened gradually if no more trouble developed.

It was unclear how far the new military rulers, imbibed in the ascetic traditions of South Korea's well-drilled Army, meant to go in rooting out corruption. Several present and former public officials with suspect fortunes remain untouched, and lower level corruption has become part of the system. A homeowner wanting to shorten the two-year waiting period for a new phone, for instance, routinely pays an extra $50 to shorten the wait to three months.

In addition to Kim, who was charged with acquiring $36 million in farms and newspaper properties through corrupt means, the accused officials included former South Korean Central Intelligence Agency director Lee Hu Rak, former Army chief of staff, Lee Sae Ho, Kim's brother Jong Nak, and former treasurer of Kim's party, the Democratic Republican Party, Kim Jin Man.

Others were former presidential bodyguard Park Chong Kyu, National Assembly member Lee Byung Heui, former presidential secretary Oh Won Chol and former Veterans Administration Director Chang Dong Woon.