Diclofenac potassium was synthesized from aniline and chloroacetyl chloride. The reaction of diclofenac potassium with calcium sulphate dihydrate and ammonium sulphate yielded diclofenac calcium and diclofenac ammonium, respectively. After diclofenac potassium was acidized with hydrochloride, the esterification of attained diclofenac with absolute methanol and absolute ethanol yielded compounds diclofenac methyl ester and diclofenac ethyl ester, respectively. Among the five compounds, diclofenac calcium and diclofenac ammonium are new compounds, and their synthetic methods have not been reported in the world. Every synthesized compound and intermediate were measured their 1H-NMR, 13C-NMR spectra. Analgesic activity of the target compounds was screened using acetic acid writhing test of mice and anti-inflammatory activity of the compounds was tested by xylene-induced ear swelling of mice. The results showed that all the 5 compounds had strong analgesic activity and anti-inflammatory activity. Among them, diclofenac methyl ester is the strongest, its analgesic and anti-inflammatory effects were stronger than the clinical use of diclofenac potassium.