The pattern of daily activity of the Eurasian lynx Lynx lynx L. was studied by radio-telemetry in the Białowieża Primeval Forest (eastern Poland). Radio-tracking of 18 lynx was done by 24-h continuous observations and by sampling on a daily basis. Lynx were active mostly at night. There was generally one peak of activity between 15:00 and 07:00 which, however, decreased slightly between 20:00 and 22:00. On average, lynx were moving for 6.5 h/day. In males, 73% of locomotory activity occurred at night, whereas females were active as long during the daylight as during the night. Movement bouts of females were shorter than those of males (1.1 h vs 2.1 h) but more frequent (4.2 vs 3.0 bouts/day). General patterns of activity of females with and without kittens were similar. However, females with kittens were active twice as long per day than non-reproducing females. In May–August (intensive care for kittens), reproducing females were active 26% longer than in September–April. Non-reproducing females showed the opposite pattern; they were active 60% less in May–August compared with September–April. Locomotory activity of adult males was 30–70% longer in January–March (mating season) than in other seasons. The pattern of lynx activity was shaped predominantly by searching for and consuming large prey. The lynx were active for the longest time during the days when they searched for prey but made no kill (12.5 h/day on average) and for the shortest time on the first day after killing a deer (1.6 h/day). Their moving activity increased steadily in the following days, reaching 6.8 h/day on the fourth day of consuming a killed deer. Ambient temperatures and rainfall did not significantly affect lynx activity, but there was little movement most of the time in heavy rain, and all day when the temperature was above 30 °C.