TOKYO (AP) _ Prime Minister Kiichi Miyazawa's party easily won a seat in Parliament's upper house Sunday in a by-election in which the party faced little opposition.

Other recent by-elections have been closely watched for signs of how Miyazawa's Liberal Democratic Party will do in national elections in July for the upper house.

Since Miyazawa became prime minister last November, his party has lost two by-elections. In both cases, the party was hurt by scandals over alleged influence peddling or questionable political donations.

In Sunday's by-election, the Liberal Democratic Party's Yasu Kano, 57, was opposed only by Tatsuo Nara, 59, of the Communist Party in the race in Ibaraki prefecture, or state. He won 357,271 to 104,352, the election committee said.

The No. 1 opposition party, the Socialists, did not field a candidate, apparently because Ibaraki, immediately north of Tokyo, is regarded as a stronghold of the conservative governing party.

The by-election was held to fill a vacancy left by the death of Mrs. Kano's husband, Akio, in February.

The victory left Miyazawa's party with 114 of the 252 seats in the upper house.