Belonging to the field of building materials, the invention relates to a 
cement composite shape-stabilized 
phase change material 
mortar, a preparation method and application thereof. The 
mortar comprises a shape-stabilized 
phase change material with a particle size of less than 2mm, 
cement and sand, wherein the shape-stabilized 
phase change material is formed by taking a paraffin substance as the main heat storage agent, and using 
high density polyethylene, a 
styrene-butadiene-
styrene triblock 
copolymer and expanded 
graphite as an encapsulation support, and the 
cement accounts for 20%-25% of the total 
dry weight, the shape-stabilized 
phase change material accounts for 50%-60% of the 
dry weight, and the water adding amount accounts for 27%-33% of the 
dry weight. The invention also provides a preparation method. The cement composite shape-stabilized 
phase change material mortar provided by the invention can be directly applied to the building wall surface, or be pasted on the building wall surface after being cast in situ into a precast slab to form a composite phase change heat storage wall so as to improve the heat storage capacity of the 
building envelope structure. The cement composite shape-stabilized 
phase change material mortar provided by the invention has the advantages of wide material sources, low cost, good storage durability, and wide application range.