A field experiment was conducted to investigate the effect of wheat straw return ways on maize production and greenhouse gases (GHGs) mitigation in North China Plain. GHGs emission was measured using static-chamber gas chromatography method. Five treatments were established, including CK (no chemical fertilizer+no straw as control), NR (chemical fertilizer+no straw), SR (chemical fertilizer+straw), AR (chemical fertilizer+straw as ash), BR (chemical fertilizer+straw as biochar). The results showed there was no significant change in the dynamics of greenhouse gases emission from soil among different treatments, but significant in the amount of emission, which was related to types of greenhouse gases. The amount of CO_2 emission in the treatment of SR increased by 29.7%, 17.5% and 31.7% compared to the treatment of NR, AR and BR, and the amount of NO_2 emission in the treatment of SR increased by 78.1%, 76.3% and 114.0% compared to the treatment of NR, AR and BR, respectively, but there was no significant difference in the amount of CH_4 emission among the all treatments. The GWP was decreased by 28.7% in the BR treatment than that in the SR treatment, but no difference among the BR, NR and AR treatment.Considering the result of corn yield into account, the GHGI was decreased by 4.9% and 14.9% for the treatment of BR than the treatments of NR and AR, and significantly was decreased by 36% for the treatment of BR than the reatment of SR. Therefore, the conversion of crop straw to biochar as an addition to dryland could be an effect way of increasing maize yield and mitigating climate change.