Background: Persistent methamphetamine (METH) psychosis is a psychotic state beyond 1-month after abstinence, for which there is no effective treatment. This study aimed to evaluate the effectiveness of electroconvulsive therapy (ECT) in persistent METH psychosis patients hospitalized at Shahid Beheshti Hospital, Kerman, Iran, from 6 September 2012 until 6 September 2013, who were not remitted after treatment with olanzapine. Methods: This research was a pilot study on hospitalized patients. After 4 weeks of treatment with olanzapine, 10 out of 71 studied patients did not show complete remission of psychotic symptoms despite their response to the treatment. The mentioned 10 patients were divided into 2 groups by random digit numbers. 5 patients had continued olanzapine and other 5 received 6 sessions of bilateral ECT every other day in addition to olanzapine. Findings: Remission rate of patients in the initial 4 weeks was 78.7%. Reduction in total brief psychiatric rating scale (BPRS) scale at the end of 1-week compared with the next week demonstrated improvement in the symptoms until the end of the study. There was no significant difference in BPRS scores between weeks 4 and 6 in the two groups. Conclusion: This research demonstrated that few sessions of ECT in persistent METH psychosis will not lead to remission in all patients.