Phencyclidine (1-(1-phenylcyclohexyl) piperidine, CAS 956-90-1, PCP, I) and its derivatives have shown many analgesic effects. In this research, a new derivative of PCP (1-[1-(2-methylphenyl) (cyclohexyl)l3-piperidinol, PD, II) was synthesized and its analgesic (acute and chronic pains) effects were examined on rats using tail immersion (as a model of acute thermal pain) and formalin (as a model of acute and chronic chemical pain) tests and the results are compared to PCP and control groups. The results indicated that II produces higher analgesic effects in the tail immersion test compared to the PCP and control groups, with a marked and significant increase in tail immersion latency for the doses 1, 5 and 10 mg/kg. The formalin test showed that PD (II) is not effective in acute chemical pain (phase I, 0-5 min after injection) in all doses but chronic pain (initial-phase II, 15-40 min after injection) is significantly attenuated by this compound compared to PCP and saline (control) in dosesof 5 and 10 mg/kg. It is concluded that II is effective in acute thermal (in all doses) and chronic (doses of 5 and 10 mg/kg) pains; however, it is not effective in acute chemical pain compared to PCP and control.