Acrylic acid (AA)/ammonium allylpoly(ethylene glycol) sulfate (AS10, 10 is the degree of polymerization of polyethylene glycol) copolymers, as non-phosphorus antiscalants for calcium-phosphate precipitation, were synthesized by using of AA and AS10 monomers and ammonium persulfate initiator. The copolymer of AA/AS10 was characterized by FT-IR. Through single factor test, the optimal synthetic conditions were obtained as follows: mass ration of AS10 to AA was 2:1, dose of initiator accounted for 3% of the total monomer mass, reaction temperature was 80 ℃, and polymerization time was 1.5 h. The influence of dose of AA/AS10 on calcium-phosphate inhibition was also investigated. It was shown there is a threshold dose and approximately 92% calcium-phosphate inhibition when the dose of AA/AS10 is 6 mg•L-1. Scanning electron microscope (SEM) images showed the application of AA/AS10 inhibitor significantly decreased the size of calcium-phosphate solids thereby dispersing through water.