Leftist members of the European Parliament tried unsuccessfully today to block President Reagan's speech to the assembly on Wednesday for the 40th anniversary of V-E Day and announced that they would seek other ways of protesting the visit.

A procedural amendment designed to prevent Reagan from addressing the parliament, a directly elected body representing 10 European Community countries, was mounted by British Socialists with support from some Communists and members of the West German Greens party. It was defeated by 147 votes to 38 after a stormy, 45-minute debate.

The procedural debate on whether to allow Reagan to speak reflected concern among left-wing members of the parliament over the way in which the invitation to the U.S. president was handled.

Some Socialist deputies who opposed the anti-Reagan motion said privately that they were worried by the lack of consultation about the arrangements for the visit.

"Wednesday is not going to be a very easy day for the European Parliament," predicted Katherina Fokke, the leader of the 131-member Socialist group, the largest political faction in the assembly.

Opponents of Reagan's visit were divided over how to demonstrate their disapproval of the U.S. president. Some said they planned to boycott his address, while others said they would wear badges protesting the U.S. embargo against Nicaragua and the administration's policies on arms control.

Reagan's 30-minute address to the European Parliament has been billed by the White House as one of the most important events of his four-nation European tour. The president is likely to use the occasion for a major policy statement on postwar reconciliation in Europe and U.S.-European relations.

Right-wing and centrist members of the assembly have welcomed Reagan's decision to spend May 8 here.