Uneasy about expanding Soviet naval power, Japan may buy antisubmarine patrol planes from the Lockheed Aircraft Corp. although the California-based manufacturer's last major sale here caused a major cooruption scandal.

Last year, Lockheed admitted making $12 million in secret payments to push sales of the Tristar jetliner. Former Prime Minister Kakuei Tanaka, accused of receiving $1.6 million in bribes, is among those on trial.

Japan is preparing to do business with Lockheed again, defense agency officials indicated today, because its P-3C Orion is the best aircraft for tracking Soviet nuclear submarines.

Final decision on purchase of up to 80 patrol planes will be made next month. Vice Defense Minister Koh Maruyama said today, and the Orion is the leading candidate. "We are not thinking of any other plane," explained a Defense Agency source, "but because of the Lockheed scandal we have to take political considerations into account.

A defense white paper published today emphasized the urgency of replacing the World War II vintage planes now used to track submarines.

"Hidden in the ocean depths and operating secretly, submarines can pose a great threat to a Japan dependent on trade for its livelihood and overseas sources for most of its resources," the report stated. The planes now in use were called "partially or wholly inadequate."

Although the white paper did not specify the nationality of submarines that might pose a threat, the Defense Agency sources said the Soviet Far East fleet was the source of their concern. Operating from Vladivostock, the Soviet navy has increased its strength in recent years, evolving from a coastal force to a deep-water fleet.

Heavily dependent on its sea-lanes for oil, food and raw materials, Japan feels particularly threatened by the increase in the Soviets' Pacific submarine force from 130 to 165 over the last four years. Forty-five of the subs are nuclear-powered - both strategic missile carriers and hunter-killer boats - that are able to travel fast, deep and stay submerged indefinitely.

"It is imperative that the next antisubmarine aircraft be selected as soon as possible in order to maintain the necessary antisubmarine capability," the report urged.

Defense experts began the process of choosing a new antisubmarine plane 10 years ago. Budgetary constraints and the strong pacifist sentiments that oppose any increase in the efficiency or numbers of the self-defense forces caused delays. There was also pressure from industry and some government circles to develop a new plane in Japan to help the domestic aircraft industry.

In 1972, Prime Minister Tanaka ordered a review of the selection process that set back the eventual decision by two or three years. The Defense Agency had again resolved that the P-3C was the best choice when the bribery scandal broke in February, 1976, making another deal with Lockheed temporarily out of the question.

Were there an easy alternative to the Lockheed product, Defense Agency officials still say they would take it but the P-3C is the U.S. Navy's standard antisubmarine weapon and has been gently pushed by the United States in a campaign to get the Japanese to accept more responsibility for their maritime defense.

The Japanese are considering manufacturing the plane here. Estimates are that it would cost $23 million per plane to buy from Lockheed while making them in Japan would push the cost to $31 million.

Political problems surround the choice of any weapons system in Japan. The fear of militarism and bitter memories of the World War II defeat have left the Japanese public deeply resistant to an increase in the defense establishment. The country maintains only skeletal self-defense forces to handle "limited and small-scale aggression."

Today's white paper marks another deliberate step in the Defense Agency's long-term plan to try to convince the public of the necessity for a high-quality, adequate defense. Military spending is currently .88 per cent of the gross national product and the government has ruled it shall not rise above 1 per cent. The United States spends 7 per cent of its GNP on defense.

The absence of an obvious military threat has handicapped those interested in beefing up the self-defense forces.