Temperature and the raw materials can influence biochar properties, and biochar can affect the N₂O emission from soil. This study is to screen the biochar suitable for Latosol in Hainan. Four Hainan gramineous plant materials were selected to produce biochars under 300℃, 500℃ and 700℃, respectively, and then the effects of the 12 types of biochars on Latosol properties and N₂O emission were studied with the indoor cultivation. The results showed that all biochars significantly increased soil pH value, promoted the contents of soil organic carbon, available phosphorus and rapid available potassium, and accelerated soil nitrification. Soil N₂O emission was promoted by biochars derived under 300℃ but was inhibited by biochars derived under 500℃ and 700℃. Among all plant materials, soil N₂O emission of bagasse biocgars derived under the pyrolysis temperature was the lowest, which is possibly due to the stable carbohydrate in the bagasse after sugar extraction. On the whole, the bagasse biochar derived under 500℃ is recommended to soil improvement, which is more conducive to less N₂O emission in tropical Latosol soil.