Ford Motor Co. announced yesterday that it is considering a takeover of Alfa Romeo Auto S.p.A., one of Italy's premier sports-car manufacturers.

"Ford has expressed an interest in acquiring substantial equity in Alfa Romeo that could lead to a majority position" in the company, said Kenneth Brown, a Ford spokesman in Dearborn, Mich.

"We've agreed with them to kick off a joint study" of merger possibilities, Brown said. The study is expected to last two months, the spokesman said.

"Preserving Alfa Romeo's unique Italian identity" would be a key requirement of any proposed merger between the two companies, Ford said.

A Ford-Alfa Romeo merger would mark the second successful attempt by an American auto maker to acquire majority interest in a prestigious European car company. General Motors Corp. this year acquired 87.5 percent of Lotus Cars Ltd. of Britain, which produces expensive sports cars.

The acquisition cost GM nearly $40 million, according to company and auto industry sources.

Chrysler Corp., the nation's third-largest auto maker after GM and Ford, has a 5 percent interest in Officine Alfieri Maserati S.p.A., another producer of expensive Italian cars.

Maserati will build 5,000 luxury sports cars annually for Chrysler. The cars, which will cost about $30,000 each, are scheduled for U.S. introduction "sometime in 1987," a Chrysler spokesman said yesterday.

"Everybody among the domestic auto makers wants to have a prestige car," said Arvid Jouppi, an independent auto industry analyst based in Detroit.

European-designed cars are the most prestigious models in the luxury segment, Jouppi said.

Domestic car companies "have been looking for somebody in Europe who they could work with to reduce overhead," said Charles J. Brady, an analyst with New York-based Sanford C. Bernstein & Co. Inc.

U.S.-market cars coming from a Ford-Alfa Romeo merger "would be limited in number, but high in profit," Brady said.

Alfa Romeo, on the other hand, would benefit from a Ford merger by gaining a stronger distribution system for its products in the United States, analysts said. Alfa Romeo currently sells the GTV-6 Graduate Convertible and the Spider Veloce in this country. Sales of both have been hampered by a relatively weak distribution and service network, according to analysts. At the same time Alfa Romeo is struggling to keep its head above water in Europe, the analysts said.

For example, Alfa Romeo last year held 1.5 percent of the European auto market, selling about 150,000 of the nearly 10 million cars sold there, according to industry figures.

Ford was the third-largest seller in Europe with 12.1 percent of that market in 1985.

Italy's Fiat Auto S.p.A. was second with 12.4 percent of the European market, and West Germany's Volkswagenwerk A.G. was first with 12.8 percent. GM came in fifth, behind France's Automobiles Peugeot, with 11.5 percent of the 1985 European car market.