OBJECTIVE: To evaluated the benefits of oral administration of arsenic-containing Qinghuang Powder (QHP) compared with decitabine for patients with high/very-high (H/VH) risk myelodysplastic syndrome (MDS) according to the Revised International Prognostic Score System. METHODS: The OS (mOS) rate, annual OS rate and progression to acute myeloid leukemia (AML) in patients with H/VH MDS treated with QHP (QHP group, n = 27) and decitabine (decitabine group, n = 20) were retrospectively analyzed. The effects of prognostic factors of age, proportion of bone marrow blast, peripheral blood cell count, karyotype and Charlson Comorbidity Index (CCI) on OS were further analyzed. RESULTS: The mOS rate of QHP group (29 months) was significantly longer than that of the decitabine group (18 months) (P = 0.043). The OS rates of 1, 2, and 3 years were significantly higher in the QHP group (88.9％, 59.3％, 29.6％) than that in the decitabine group (70％, 25％, and 5％)(P = 0.01). There was no significant difference of 5-year OS rate between the 2 groups (P = 0.133). The effects of prognostic factors on mOS were further analyzed, and it was found that there was no significant difference of mOS rate between the QHP group (29 months) and the decitabine group (21 months) in the patients with age 65 years old (P = 0.673). The mOS rate was significantly longer in QHP group (28.5 months) than that in decitabine group (18 months) in the patients with age of < 65 years old (P = 0.04). The proportions of bone marrow blast cells with 10％ or < 10％ had no significant effects on the mOS rate of patients in the 2 groups (P = 0.429, P = 0.183). In patients with HGB 80 g/L, mOS rate was significantly longer in the QHP group (57 months) than that in the decitabine group (21 months) (P = 0.047), while in patients with HGB < 80 g/L, there was no significant difference of mOS rate between the 2 groups (P = 0.265). In the patients with PLT < 50×109 /L, the mOS rate was significantly longer in the QHP group (33 months) than that in the decitabine group (16 months) (P = 0.028). In the patients with PLT 50×109 /L, there was no significant difference of the mOS rate between the 2 groups (P = 0.338). In the patients with ANC < 0.8×109 /L, the mOS rate was significantly longer in the QHP group (20 months) than that in the decitabine group (7 months) (P = 0.014). In the patients with normal karyotype, the mOS was significantly longer in the QHP group (32 months) than that in the decitabine group (15 months) (P = 0.009). In the patients with abnormal karyotypes, there was no significant difference of the mOS rate between the 2 groups (P = 0.882). In the patients with good karyotypes, the mOS rate was significantly longer in the QHP group (37 months) than that in the decitabine group (20 months) (P = 0.019). In the patients with moderate/poor/very poor karyotype, there was no significant difference of the mOS rate between the 2 groups (P = 0.685). In the patients with CCI 3, the mOS rate was significantly longer in the QHP group (34 months) than that in the decitabine group (10.5 months) (P = 0.017). In patients with CCI < 3, there was no significant difference of the mOS rate between the 2 groups (P = 0.581). The proportion of progression to AML in the QHP group (18.8％) was significantly lower than that in the decitabine group (25％) (P = 0.03). CONCLUSION: Compared with decitabine, oral administration of arsenic-containing Qinghuang Powder could help patients to survive longer and decrease incidence of progression to acute myeloid leukemia in the treatment of patients with high/very high MDS.