Attended Žeimelos elementary school. He sang in the choir of the Žeimelis church and learned to play the organ from its director, Juozas Pėželis. Later, he got the position of organist in the parish of Kyburii (Pasvalis district).
1937-1939 served in the Lithuanian army and led the soldiers' choir. 1939-1944 At the Šiauliai Music School, he studied the organ (teacher Juozas Karosas), strict viola (teacher Povilas Matiukas), playing the piano (teachers I. Prielgauskas and Julius Gaidelis) and music theory disciplines (teacher J. Karosas). While studying, he played viola in the school's school student string orchestra (conductor J. Karosas) and in the symphony orchestra of the city musical theater (conductor Petras Armonas).
Since 1940 studied at the Šiauliai adult gymnasium, 1944. graduated from the Šiauliai boys' high school as an external student.
1944-1948 studied composition at the Kaunas Conservatory (class of Prof. Juoz Gruodis), which he graduated with honors. 1946-1948 led the student choir of the Lithuanian Physical Education Institute, various vocal ensembles.
1949-1952 studied composition at the postgraduate school of the Leningrad N. Rimsky-Korsakov State Conservatory (prof. V. Voloshinov's class). in 1954 defended his candidate's thesis "Lithuanian folk song in the symphonic works of some Lithuanian Soviet composers", and in 1972 - doctoral dissertation "On the matter of chord structure". J. Juzeliūnas studied the folklore of Lithuanian music, compiled its classification system according to the supporting tones of the melodies; also researched non-European musical cultures, for which purpose he visited African and Asian countries.
Since 1948 – Member of the Lithuanian Composers' Union, 1954-1966. - deputy chairman of the board, later - member of the board council. Since 1957 - Docent of the Department of Composition, since 1970. - Professor, 1992-1995 - Head of the Department of Composition, educated about 50 composers. 1991-1995 was a member of the Lithuanian Science Council.
Since 1988 - Member of the initiative group of the Lithuanian Sajūdis and active participant, later - member of the Council of the Sajūdis Seimas, conducted Sąjūdis rallies. He was the chairman of the board of the commission to investigate the crimes of Stalinism (since 1991, the center for the investigation of repressions in Lithuania), 1989-1991. - People's Deputy of the Soviet Union. 1992-1993 Member of the Chief Election Commission.
in 1954 awarded to a deserving artist, 1966 - honorary names of people's artists, 1991 awarded with the Lithuanian National Prize, 1996 - Order of Gediminas 4th degree.
