WHITEHORSE, Yukon Territory (AP) _ A California businessman under indictment for illegally shipping $15 million of computer equipment to the Soviet Union was arrested by an alert mountie while on a fishing trip.

Charles McVey, who was flown to Vancouver, British Colombia, on Friday for extradition proceedings, had for several years returned from his refuge in Europe to fish at tiny, remote Teslin Lake, Canadian police said.

McVey, 64, had been on the 10 most-wanted list of the U.S. Customs Department's Operation Exodus project, which seeks to track down illegal exporters of U.S. high technology.

The former Villa Park, Calif., resident fled the United States shortly before March 1983, when a federal grand jury in Los Angeles indicted him on 23 counts of selling and shipping specialized computer equipment to the Soviet Union.

McVey is charged with using dummy companies to buy equipment such as minicomputers, satellite image processing gear and scientific equipment, based on a shopping list provided by the Soviets.

The indictment says the goods - $15 million worth - were diverted from 1977 to 1982 to institutes and military centers in the Soviet Union through a Swiss freight forwarder. If convicted on all counts, McVey faces more than 100 years in prison and a fine of up to $500,000.

A $1.2 million fine has already been levied against McVey by the U.S. Commerce Department, the second largest ever handed out under the U.S. Export Administration Act.

McVey was arrested Wednesday night in Teslin, near the British Columbia- Yukon border, said Cpl. Dan Fudge, who heads the Royal Canadian Mounted Police's two-man Teslin Lake detachment.

The 6-foot-3, 300-pound McVey surrendered peacefully when Fudge, recognizing him from a picture on file, made the arrest at a private residence in the village of 400 people about 110 miles east of Whitehorse, the mountie said.

Staff Sgt. Tom Hill of the RCMP's customs and excise division said Canadian police kept an open file on McVey, who had for several years been returning to Teslin Lake.

''He's a creature of habit,'' said Hill. ''He likes to go to the same motels and fish the same lakes.''

Fudge said he heard rumors in the community that McVey was back, saw him in a coffee shop and obtained an arrest warrant.

''We suspect that he has been in Europe - Switzerland and Malta - we just hadn't caught up to him,'' Mike Fleming, U.S. customs spokesman for the Pacific Region, said in a telephone interview from Los Angeles.

Hill said McVey is to appear in court for a bail hearing Monday.

Paul Halprin, the special Crown prosecutor handling the case, said extradition proceedings usually take up to 60 days but could take much longer if McVey appeals an extradition order through higher courts.

Two other men named with McVey in the indictment, the Swiss freight forwarder, Rolf Lienhard, and Soviet official Yuri Boyarinov, are still at large and presumed to be in their home countries.