The effects of winter temperature rises on soil microbial activity, nutrient and salinity in Ningxia Plain were studied in a field experiment using an infrared radiator to raise temperatures. Winter temperature rises led to increases in soil organic matter, available phosphorus, soil pH and total salt content, but decreased the available nitrogen in soil and the activities of soil catalase, urease and phosphatase. With a winter temperature of 0.5 °C-2.0 °C, the activities of soil catalase, urease and phosphatase were respectively decreased by 0.08-1.20 mL g^-1, 0.004-0.019 mg g^-1, and 0.10-0.25 mg kg^-1; soil organic matter was increased by 0.01-0.62 g kg^-1, available nitrogen decreased by 2.45-4.66 g kg^-1, available phosphorus increased by 2.92-5.74 g kg^-1; soil pH increased by 0.42-0.67, and total salt increased by 0.39-0.50 g kg^-1. Winter temperature rises decreased soil microbial activity, accelerated the decomposition of soil nutrients, and intensified soil salinization.