In order to explore effects of straw incorporation plus application of chemical fertilizer varying in NPK ratio on soil temperature and moisture conservation and soil-root biological properties, a field experiment was conducted. Results show that the treatments of straw incorporation plus application of chemical fertilizer varying in ratio raised soil temperature at 8:00 and 20:00 and lowered at 14:00 in all the growing periods, compared with the control. Analysis of soil temperature shows that the range of its daily variation was narrower in the treatments than in the control and the difference was significant. However, the difference was getting less significant with the increasing soil depth, which means that the soil temperature regulating effect of the treatments was declining gradually. Besides, the treatments significantly increased the populations of bacteria, actinomyces, fungi, ammonia-oxidizing bacteria, aerobic authigenic nitrogen-fixing bacteria, nitrite bacteria, phosphorus bacteria and aerobic cellulose decomposing bacteria, but generally the difference between the treatments in the effect was not significant. All the treatments, except Treatment SNP₁ (3 000 kg hm^-2 crushed straw 150 kg hm^-2N 75 kg hm^-2 P₂O₅), were higher than the control in activity of catalase, urease and invertase, but the differences were not very significant. The findings demonstrate that straw incorporation plus application of chemical fertilizer, though varying in ratio, may reasonably regulate, increase the population and activity of soil microbes and help improve the soil eco-environment. Among the treatments, Treatment SNPK₁ (3 000 kg hm^-2 straw 150 kg hm^-2 N 75 kg hm^-2 P₂O₅ 37.5 kg hm^-2 K₂O) and Treatment SNPK₂ (3 000 kg hm^-2 straw 225 kg hm^-2N 112.5kg hm^-2 P₂O₅ 56.3 kg hm^-2K₂O) are the most significant in this effect.