This study aimed to determine the effect of breed and season on the semen quality of AI bulls. The material used was n= 78,648 records of ejaculated semen from 85 Limousine and 88 Simmental bulls collected between period 2010 and 2020. Semen qualities evaluated in the study were: ejaculate vol-ume (Vol), pH, individual sperm motility (ISM), sperm concentration (SC), and post-thawing motility (PTM). The data was analyzed by using a MIXED model with breeds and seasons as fixed effects and animals as random effects. The seasons were significant (p