Using water as solvent and sodium hydroxide as green grafting agent, three modified Polyaspartic acid (PASP) scale inhibitors, β-PASP, were synthesized by ring-opening modification of the intermediate polysuccinimide (PSI) which used three β-dicarbonyl compounds as their grafting reagents. The structure of β-PASP was characterized by Fourier transform infrared spectroscopy (IR). The optimal synthesis conditions of PSI were investigated by orthogonal experiment. According to the optimized conditions, the scale and corrosion inhibition performance of β-PASP were also evaluated respectively. The optimum synthesis process of β-PASP were summarrized as follow: the n(PSI): n(β-dicarbonyl compound): n(NaOH)=1:0.6:6, the reaction time was 18~24h, the grafting reaction temperature was 35°C and the mass fraction of raw material was 15%. Experimental results demonstrated that three modified PASP ex-hibited more excellent scale inhibition property against CaCO3 than PASP, and the scale inhibition efficiency can reach 100% when the mass dosage was 8~10 mg/L. At the same time, β-PASP inhibitors possesses better corrosion inhibition properties on A3 carbon steel than PASP.