The aim of the study was recording the changes in behaviors and performance of Japanese quails "Coturnix japonica" due to circadian rhythms and different light duration. A total of 220 Japanese quail chicks was used and distributed to 2 experiments (100 birds to record the effects of circadian rhythms and 120 birds in the lighting duration study). The behaviors were recorded by direct observation and video recording. It was found the significant differences in the most of recorded behaviors among the different day times, especially in video recording. Where, the ingestive and kinetic behaviors were significantly higher at morning time, while the resting behavior was the highest in midday with significant differences. Comfort behavior was significantly lower at morning time than others. In the current study, the lighting duration had significant effects on ingestive and kinetic behaviors, where it was the highest in 24 hours of lighting duration. While the dust bathing was significantly higher in 14 hours of lighting duration. On the other hand, there were no significant differences in all growth performances of quails kept in two different light duration. It was concluded that, the changes in day times and lighting duration of quails associated with significantly difference normal behavior