Background: Hemp seed (HS) has high protein with good quality and more than 90% of its fats are polyunsaturated fatty acids.

  Objective: The objective of this experiment was to determine the effects of graded levels of HS on performance, organ weight (OW), and serum cholesterol levels on broilers.

  Methods: 192 male broiler chicks (1 d old-ROSS 308) were randomly assigned to a completely randomized design with 4 dietary treatments: control (without HS), 2.5, 5 and 7.5% HS in 4 replications (12 birds/pen). Weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) were measured and calculated at the end of each wk. At the end of 6^th wk, to determine serum lipids (1 bird/pen) and OW (2 birds/pen) were randomly selected.

  Results: WG on 0 – 21 d (p<0.01) and 0 – 42 d (p<0.05) were significantly affected by HS levels. Increasing dietary HS levels significantly decreased total cholesterol, LDL, VLDL, triglyceride and liver weight relativity percentage (p<0.05) and increased HDL (p<0.01) levels in serum. HS levels had no significant effect on WG 22 – 42 d, FCR, FI and other organs weight relativity percentage (p >0.05).