The invention belongs to the field of bone tissue replacement materials, and relates to a porous hydroxyapatite ceramic/graphene composite bone tissue replacement material and a preparation method thereof. The preparation method of the hydroxyapatite ceramic/graphene composite bone tissue replacement material sequentially comprises the steps of preparing nano hydroxyapatite/chitosan/graphene slurry, preparing porous hydroxyapatite/graphene composite stent, and sintering molding, wherein a method for preparing the composite stent comprises the steps of immersing polyurethane sponge in the hydroxyapatite/chitosan/graphene slurry, squeezing the polyurethane sponge to fill pores in the polyurethane sponge with the slurry, and vacuum-drying the polyurethane sponge, wherein during vacuum drying,the vacuum temperature is 40-80 DEG C, and the vacuum degree is 60-90 KPa. The bone tissue replacement material has a porous structure and high mechanical strength and porosity, and can meet the requirements of bone tissue replacement materials.