Abstract: A modified method was established for the determination of chromium in capsule shells by ultrasonic wave digestion-graphite furnace atomic absorption spectrometry.After the atomic absorption spectrometry method for determination of chromium parameters optimization,the best test condition is digestion in 200 °C and 500 °C，pyrolysis in 1 100 °C，and atomize in 2 150 °C.Under the optimum testing conditions,the detection limit of chromium is 0.05ng/mL and sample recovery rate of 93％-106％.The modified method was quick and accurate compared with traditional methods.