Yuri Balovlenkov, 33, ended his 42-day-long hunger strike yesterday after he was assured by authorities that he would be allowed to join his wife and daughter in Baltimore.

Balovlenkov, a computer specialist, has been trying for three years to join his wife, Elena, a staff nurse at City Hospitals, and their 2-year-old daughter, Katya, whom he has never seen. He and four other Soviet citizens seeking to join their spouses in the West started a joint hunger strike on May 10 to press their cases.

Other members of the group had earlier abandoned their fast, three of them after having been promised exit visas and the fourth halting the protest on the advice of West German diplomats presumably after they received indications that he would be permitted to join his wife in West Germany.

Balovlenkov said he expected to leave for the United States as soon as he regains his strength. He lost 50 pounds during his 42-day fast.

His wife said she expects to hear from Russian Embassy officials whether they will grant her a visa to visit the Soviet Union.

She said her husband will be taken to a Baltimore hospital when he arrives in the United States.