In 2019, Pirmanov signed the largest advertising contract with 7SABER
brands of
Uzbekistan. Pirmanov's professional debut was twice postponed; once due to the
COVID-19 pandemic and another after Pirmanov contracted
COVID-19. On February 14, 2021, he made his professional debut against
Asror Sotvoldiev at the Lokomotiv Sports Palace in
Tashkent and won early. Two judges scored the bout 20–20 while the third scored it 20–20. His second fight for the defense of the
WBC Asian belt took place one month later, on March 14, at the Sports Club Hall in
Asaka,
Andijan region, and he defeated
Khumoyun Rustamov by technical knockout (TKO) in the fourth round. On May 29, 2021, Pirmanov entered the ring against Rauf Agayev from
Azerbaijan at the "Universal" sports palace in
Tashkent. Pirmanov defeated his opponent by technical knockout (TKO). All three judges decided the fight with a score of 40–35 in favor of Islambek. On October 15, 2021, in the central stadium of the city of Kongan,
Fergana region, Pirmanov won a fight against
Russian boxer Alexander Saltikov by premature knockout (TKO). On July 15, 2022, Pirmanov defended his [World Boxing Council] (WBC) international belt against
Kyrgyzstan's Turat Osmonov at the Renaissance Hotel in
Tashkent, Pirmanov won by technical knockout (TKO). On January 29, 2023, Pirmanov defeated
Thai boxer
Namphon Nonthafani by technical knockout (TKO) in the first round. ==Professional boxing record==