In this paper, Ni was determined in biological samples such as blood, serum and urine by HGAAS. This method was simple, rapid, good precision and high accuracy. The sensitivity of blood, serum and urine is 0.48 microgram.L1, 0.24 microgram.L1, 0.50 microgram.L1. The relative standard deviation is 2.9-5.4% and the recovery is 71-103%.