In order to improve road performance of emulsified asphalt cold recycled mixtures in south China moist hot areas, the effects of emulsified asphalt content, cement content and reclaimed asphalt pavement（RAP）content on high temperature performance, water stability and fatigue property of cold recycled mixtures were studied. Based on multi index weighted method, the performance of cold recycled mixture and its influencing factors were optimized, the anti cracking enhancement mechanism of cement emulsified asphalt mortar was revealed by scanning electron microscopy. The results show that high temperature performance of cold recycled mixtures is mainly affected by emulsified asphalt dosage and cement content, while water stability is significantly affected by RAP content, and the fatigue property is significantly affected by various factors under different stress ratios. When the emulsified asphalt dosage is 35%（by mass, the same below）, the cement content is 20% and the RAP content is 80%, the overall performance of cold recycled mixtures reaches the best. The cement emulsified asphalt mortar can improve the micro interface deformation coordination of cold recycled mixtures, make it better to transmit and disperse the stress, and slow down the crack development rate which is remarkable for crack resistance.