The present study focuses on the assessment of porcine endogenous retrovirus (PERV) release from PK15 cells in a time dependent manner. The highest amount of PERV A RNA was detected in PK15 cells after 16 hours of culture. The highest amount of PERV B RNA was detected in PK15 cells after 20 hours. The highest amount of both subtypes RNAs was detected in culture medium after 32 hours of culture. The peaks of PERV reverse transcriptase (RT) activity were detected after 28 h of culture in PK15 cells and after 32 hours in the culture medium. The monitoring of PERV release from PK15 cell line may be useful for the evaluation of PERV replication.