Abstract: The characters of ecological environment of soil under rice straw mulch for many years in organic tea plantation were studied. The results indicate that the rice straw mulch can improve the nutrient regime of soil. The contents of organic matter, total nitrogen, total phosphate, and available nitrogen, phosphate, potassium of 0～40cm soil under rice straw mulch are 2.00 times, 1.87 times, 1.66 times, 1.91 times, 1.91 times, 2.56 times, respectively, of those of the check. The rice straw mulch can increase the amount of soil microoganism. The amounts of fungi and bacteria of 0～40cm soil under rice straw mulch are 3.54 times and 4.46 times, respectively, of those in the check. The rice straw mulch can improve the water status of soil in dry season. The water contents of 0～10cm, 10～20cm and 0～30cm soil layers under rice straw mulch are increased by 26.24%, 13.92% and 12.38%, respectively, compared to the check. The rice straw mulch can improve the animal conditon of soil. The total amounts of soil animals of 0～40cm soil layer under rice straw is 1.87 times of that of the check. Therefore, the rice straw mulch should be energetically expanded in organic tea plantation.