Objective To investigate effects of driving fatigue on working memory. Methods The control group included 12 taxi drivers after adequate rest while the fatigue group included 27 taxi drivers who had been driving for 10h. Digit memory span, words span, Digit Subtraction Test, Random Number Generation test were used. Results Compared with the control(6.60 ±0.40,90.67 ±6.65,158.27 ±29.12,0.30 ±0.06,24.29 ±10.59,35.90 ± 10.64 ), driving fatigue group were significantly( P ＜ 0.05 )different in the number of backward number memory span( 5.37 ± 0.72 ), percentage of number of right reaction of the number of total reaction of Digit Subtraction Test(79.95 ± 8.04), total number of RNG( 88.33 ± 19.48 ), RNG(0.40 ± 0.05 ), Coupon( 12.35 ±12.88), NSQ(49.72 ± 8.06). Conclusion Driving fatigue can decline the working memory.