In in-situ and non-situ modes, new GIFT tilapia (Oreochromis niloticus) was cultured with biofloc technology (BFT) for 120 d. Initial body mass of tilapia was (19.76±2.44) g, (21.01±1.23) g, and initial culture density was (2.63±0.33) kg/m³, (2.80±0.17) kg/m³. At the end of the experiment in situ group (control group) and non-situ group (treatment group),the weight of experimental fish were (306.21±18.64) g, (338.49±19.35) g. The culture density reached (33.29±0.83) kg/m³, (37.99±2.34) kg/m³. Ammonia nitrogen and nitrite nitrogen were accumulated in the early stage, but in the middle and late stages, the concentration of ammonia N was maintained below 3 mg/L and nitriter N maintained below at 2 mg/L. Nitrate nitrogen concentration has been accumulated in the whole experiment. The water quality of the treatment group was more stable than that of the control group. There was no significant difference in crude protein concentration between the two groups. There was no significant difference in stomach protease activity in each period, but the final activity was slightly lower than the initial activity. The trypsin activity in the intestinal tissues of the control group was higher than that in the treatment group during the whole breeding period. There was no significant difference in stomach lipase activity and intestinal lipase activity in the two groups.The experiment provides reference for the application and improvement of biofloc technology in production practice, through studying the effects of two kinds of bioflocculation modes on the production of new GIFT tilapia.