TOKYO, March 10— Kim Il, First Vice President of North Korea, died Friday after a long illness, the North Korean Central News Agency reported. He was 73 years old.

Mr. Kim had spent much of 1982 receiving medical treatment in Rumania and missed several important ceremonial events in 1983.

In a report monitored in Tokyo, the agency said a state funeral would be held Sunday for Mr. Kim, who was in the inner circle of early revolutionaries who fought the Japanese colonial occupation with the North Korean leader Kim Il Sung.

Kim Il was a member of the Central Committee of the Communist Party and of the National Administration Council, the agency said.

Born on March 20, 1910, in Hambyong Province, Kim Il joined the underground Communist Party in 1932 and fought the Japanese from 1935, the agency said. Japan's colonial occupation of North Korea began in 1910 and ended in 1945.

During the Communist struggle for power, Kim Il served in different military posts and then became First Deputy Prime Minister in 1959, Prime Minister in 1972 and Vice President in 1976, the agency said.