Objective We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy of cognitive stimulation therapy (CST) of different durations for Alzheimer's disease (AD). Methods A comprehensive search was carried out in three databases. The primary outcome was Mini-Mental State Examination (MMSE) score. We conducted a meta-analysis with Review Manager, version 5.3 and assessed the methodological quality of the included studies using the Cochrane Collaboration Recommendations assessment tool. Results Treatment effects from the meta-analysis showed that CST plus acetylcholinesterase inhibitors (ChEIs) was better than the control assessed by MMSE. In addition, the meta-analysis indicated that long-term CST was better than short-term or maintenance CST. Conclusion Our study confirmed that the combination of CST and drug treatment for AD is effective in AD, regardless of whether short-term CST, maintenance CST, or long-term CST is used. The long-term CST appears to be more effective.