This study was conducted to investigate the effect of dietary betaine supplementation on behavioral patterns and growth performance of Japanese quail. A total number of 200 healthy unsexed quail chicks with average body weight 51.80±0.66 g aged 2 weeks, were randomly assigned to 2 groups (100 birds each) and each group was subdivided into 5 replicates (20 birds each) according to the diet. The first group was fed on a basal diet without any supplementation (control group), while the second group was fed on basal ration supplemented with betaine hydrochloride at level of 1g/kg diet (betaine group). Behavioral patterns and growth performance (body weight, body weight gain, feed intake and feed conversion ratio) were evaluated for 3 weeks. The obtained results revealed that betaine supplementation had no significant effect on behavioral patterns except for crouching behavior which showed higher frequency (P=0.023)in betaine group, also betaine supplementation had no significant effect on body weight, body weight gain, feed intake and feed conversion ratio (P>0.05) of Japanese quail. It was concluded that dietary betaine supplementation insignificantly improved final body weight, body weight gain and feed conversion ratio of Japanese quail.