This 28-d feeding trial was conducted to evaluate the effects of dietary supplementation with different levels of 1,3-diacylglycerol (1,3-DAG) on growth performance, blood lipids profiles, relative organ weight and meat quality of broilers. A total of 512 male, one-d-old Ross 308 broilers with an average initial BW of 45.28 ± 0.81 g were randomly allotted to 4 treatments. Each dietary treatment consisted of 8 replicate cages, with 16 birds per replicate. The 4 dietary treatments were corn-soybean meal-based diets and supplemented with 0, 0.05, 0.10 and 0.15% 1,3-DAG, respectively. During d 1-14, with increasing the dietary 1,3-DAG levels from 0 to 0.15%, the body weight gain (BWG) was improved (linear, P<0.01), whereas the feed conversion ratio (FCR) was decreased (linear, P<0.01). During d 14-28, dietary supplementation of graded level of 1,3-DAG improved the BWG (linear, P<0.05) and decreased the FCR (linear, P<0.01). During d 1-28, there was a linear increase in BWG (P<0.01) and a linear decrease in FCR (P<0.01) with increasing 1,3-DAG supplementation. In addition, dietary 1,3-DAG supplementation tended to increase the serum HDL cholesterol levels (quadratic, P=0.074). Furthermore, the relative weight of bursa of Fabricius was increased by supplementation with 1,3-DAG (quadratic, P<0.05). In conclusion, dietary supplementation of different levels of 1,3-DAG in broilers diets could improve the growth performance, modify blood lipid profile and promote the development of bursa of Fabricius.