Borys Portnoi was born in the village of Sharovka, the Khmelnytsky region, in the family of collective farm workers. During the war his family was evacuated to Russia, in the city of Achinsk, Krasnoyarsk area; Borys was attending school there. After the demobilization of his father in 1950, the Portnois moved to Zhytomyr where six years later Borys graduated from the secondary school № 3. In 1957, after almost a year of work in the construction and installation department of SU-11 as a painter, the artist was summoned to the Soviet Army. During two years of the service, Portnoi visited the evening school of the Yaroslavl Art College. After discharging into the reserve army, the artist worked as a researcher at the Regional Ethnographic Museum of Zhytomyr, then as an artist at the local cinema "Vrozhai", combining work with studies at Zhytomyr Art Atudio. From 1962 Portnoy worked as a decorator at the "Elektrovymіriuvach" factory, and in five years he changed the place of work for the editorial office of the newspaper Komsomolska Zirka. In 1968, the artist entered the Art and Graphic Faculty at K. D. Ushinsky State Pedagogical Institute in Odessa, and next year he began to work in Zhytomyr Art and Production Workshops. Portnoi created picturesque works, decorative paintings and posters. In 1967, he became the first winner of the regional Mykola Shpak Komsomol Award for a series of posters for amateur art festivals and amateur movies.