Abstract: Abstract: Returning maize straw into soil has been demonstrated to improve soil organic matter and increase crop yields, and widely used in China. However, previous studies demonstrated that the cellulose, hemicellulose and lignin of maize straw tend to slow down the natural decay rate, thereby reducing the utilization efficiency. Consequently, this can lead to low stand establishment and reduce plant growth and yield of crops in next season, particularly in northeast China. Currently, the problem has not been solved yet regardless of being chopped or burned before returning into soil. Moreover, it is not lawful for the latter one. Therefore, effective practices for accelerating the decomposition and promoting the nutrients release of maize straw should be developed to cope with these challenges. In order to explore a more appropriate pretreatment, a successive laboratory incubation experiment was conducted in Chinese Academy of Agricultural Sciences with four pretreatments: ammoniated, acidized, microwaved and non-treated treatments. In this experiment, net bag method was used to investigate the decomposing and C, N, P and K releasing characteristics of maize straw. The results showed that the decomposition rate of maize straw were more than 50% after 100 d incubation in all treatments, especially higher decomposition rate were observed in the ammoniated and acidized treatments than those of other treatments. The decomposition rate with ammoniated, acidized and microwaved treatments was 89.22%, 91.68% and 82.26% after 300 d incubation, respectively. In contrast, the decomposition rate with non-treated treatment was 80.81%, which was lower than that of the other three treatments but significant difference was observed only among the ammoniated, acidized and non-treated treatments. Likewise, most of the C, N, P and K in maize straw have been released on the first 100 d incubation. During those days, the acidized treatment increased the N, P and K release rate by 23.95%, 13.11% and 4.27% when compared to non-treated treatment, respectively. Also, the ammoniated treatment increased the N release rate by 9.69% and the microwaved treatment increased the C release rate by 4.28% during this period. After a successive 300 d laboratory incubation, the acidized treatment was more advantageous to the release of K and P, which was 7.73% and 6.34% greater than non-treated treatment, respectively. However, the ammoniated treatment was more advantageous to the release of N and P, which was 6.16% and 5.41% greater than non-treated treatment, respectively. In this period, the microwaved treatment slightly (1.61%) increased K release rate but decreased C, N and P release rate, compared to non-treated treatment. The present results suggest that both the ammoniated and acidized treatments promoted the decomposition and C, N, P and K release rate of maize straw, especially the acidized treatment. It is should be note that microwaved treatment had no significant effectiveness even lowed the decomposition and C, N and P release rate during latter period. However, in light of the environmental difference between laboratory incubation experiment and field trail, further studies are needed to investigate the performance of different pretreatments for maize straw in the actual agricultural production.