Dihydrocumic acid was prepared from β-pinene through oxidation and dehydration. Then a series of amide derivatives from dihydrocumic acid were synthesized. Reaction conditions of dihydrocumic acid were discussed and structures of amide derivatives were characterized by IR, 1H NMR, MS, and X-ray diffraction. The antibacterial activities of these newly synthesized amide derivatives against six bacteria were also investigated by an inhibition zone method. It was shown that compounds 5a, 5b, 5d, and 5f display better anti-bacterial activities with inhibition zones 11.83, 12.33, 10.83 and 12.67 mm against Escherichia coli compared with Bromogeramine (9.67 mm), one commercially available antibacterial agent, and compounds 5a and 5d display better anti-bacterial activities against Staphyloccocus aureu compared with Ampicillin Na.