A method was set up for the determination of Zn in human urine by flame atomic absorption spectrometry with sample pretreatment by 1:4 ratio of mixture of HClO4-HNO3. The liner range is 0.1~15.0 μg/mL with the detection limit of 0.05 μg /mL and the recovery of 95.5%~106.0%. The method is reproducible and satifactory for determination of Zn in human urine.