The aim of this study was to observe and record 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 were used and distributed to two experiments (the circadian rhythms (100 birds) and the lighting duration study (120 birds). The behaviors were recorded by direct observation and video recording. The results showed significant differences in the most recorded behaviors among the different day times, especially in video recording. The ingestive and kinetic behaviors were significantly higher at morning, while the resting behavior was the highest in mid-day. Comfort behavior was significantly lower at morning than other times. The light duration had significant effects on ingestive and kinetic behaviors. It was highest in 24 hours of light duration. While, the dust-bathing was significantly higher in 14 (2.9) than 24 hours of light duration (1.74). Quails growth performance did not reveal significant differences between quails kept in 14 and 24 hours of light duration. It was concluded that, the quails on different day times and lighting duration showed significant difference on the normal behavior