The Securities and Exchange Commission yesterday charged G. Heileman Brewing Co. with insider trading violations based on the company's purchase of 105,000 common shares of Olympia Brewing Co.

Heileman did not admit to or deny the charges, but agreed to pay almost a million dollars to some Olympia stockholders.

In a suit filed in Wisconsin, the SEC charged that between April 20 and May 7, 1982, Heileman bought Olympia stock after learning from Olympia's president, Robert A. Schmidt, that Pabst Brewing Co. was interested in acquiring Olympia.

The $916,378 Heileman will return "is the largest disgorgement on an insider trading complaint from a single defendant," said Chiles Larson, a spokesman for the SEC. Heileman will pay the settlement to Olympia shareholders who sold their stock during the 2 1/2-week period.

Heileman, based in Wisconsin, is the fourth largest brewing company in the country.

Pabst, which now owns Olympia, ranks fifth.

Heileman began buying Olympia stock April 14 when Heileman Executive Vice President Robert J. Korkowski opened a confidential account for Heileman at John G. Kinnard & Co., a Minneapolis broker-dealer, to buy about 5 percent of Olympia common stock between April 14 and May 7, according to the SEC complaint.

Five days later, on April 19, Olympia's Schmidt told Heileman President Russell G. Cleary that he was scheduled to meet April 24 with Pabst President William F. Smith to discuss Pabst's interest in buying Olympia.

Schmidt also told Cleary an investor controlling a large number of both Olympia and Pabst common stock urged Schmidt to negotiate an arrangement with the Milwaukee-based Pabst, according to the SEC.

The SEC says Cleary and Schmidt discussed Pabst's offer on at least one other occasion before Heileman concluded its purchases of Olympia stock May 7.

The suit did not cover the 20,000 shares of Olympia stock Heileman bought before Schmidt talked with Cleary.

William McLucas, assistant director for the SEC division of enforcement, said the suit did not include the first week's purchase of stock because the violation occurred after Cleary's meeting with Schmidt.

"Once you come into possession of nonpublic information in such a context, you should not go forward with such a transaction," McLucas said.

Spokesmen for the SEC declined to comment on how it obtained information concerning Heileman's purchase of Olympia stock.