This study aimed to investigate the relationship between behavioural activities and sperm parameters in modern and local breeds of Ukrainian boars. Visual observations were conducted on 30 boars, aged 12 and 24 months, with five boars from each of the following breeds: Large White, Landrace, Ukrainian Meat, Pietrain, intrabreed type of Duroc breed of Ukrainian selection "Steppovyi", and the terminal line "Maxter". Behaviours such as rest, movement, feed, and water intake during 24 hours were recorded. Semen samples were manually collected from each boar and evaluated for quantitative and qualitative indicators of sperm quality and fertilizing capacity according to the "Instructions for Artificial Insemination of Pigs", which included parameters such as ejaculate volume, sperm concentration in the ejaculate, percentage of correctly motile spermatozoa, survival of spermatozoa, and fertilizing ability of boars. The study found that certain behavioural activities significantly influenced the qualitative and quantitative indicators of sperm parameters in boars of different breeds. Specifically, time spent on rest and movement, as well as the index of movement activity (at 12 months of age), significantly (P < 0.05) influenced ejaculate volume, sperm concentration, and the percentage of correctly motile spermatozoa. Moreover, the effect of these behavioural acts on ejaculate volume had a curvilinear character. On the other hand, the survival of spermatozoa and fertilizing ability of boars were mainly determined by their time spent on feed and water intake (at 24 months of age), and the relationship detected in this case was asymptotic.