Objective To study the efficacy of arsenic trioxide (ATO) combined all-trans retinoic acid (ATRA) in primary acute promyelocytic leukemia (APL) patients. Methods 98 patients with newly diagnosed APL were randomly divided into control (48 cases) and treatment group (50 cases). Control group received conventional ATRA+DA dual induction regimen and the treatment group received ATRA 25 mg·m-2·d-1, and ATO 0.15 mg·kg-1·d-1 beginning from 10 days later after administration of ATRA. After complete remission (CR), ATO and ATRA treatment were received. CR rate for consolidation, time of reaching clinical and molecular remission and 5-year disease-free survival were observed. Results CR rates were 89.6 % (43/48) and 90.0 % (45/50) in control group and treatment group, respectively, and the time of obtaining CR was (30.0±5.1) and (28.1 ±4.4) days, respectively. CR rates (x2 =-0.068, P =0.946) and time of reaching CR (t =1.757, P =0.083) in two groups showed no significant difference. In patients obtaining CR, 3 patients relapsed in 276, 385 and 394 days after CR, respectively. PML-RARα fusion gene was positive at diagnosis in all patients. The rate of negative of fusion gene at CR in control and treatment group was 25.0 % (5/20) and 29.4 % (5/17), respectively. The rate of negative of fusion gene after consolidation in control and treatment group was 92.5 % (37/40) and 97.6 % (41/42), respectively. 5-year disease-free survival rates of the control and treatment group was (85.3±5.9) % and (87.6±5.6) %, respectively. The difference was not statistically significant (x2 =0.232, P =0.630). Conclusion The regimen of ATO combined ATRA is effective in treating newly diagnosed APL patients, and can be used as an alternative regimen.