The objective of the present study is to carry out a review on the relationship between religiousness and trust via meta-analysis of conducted researches that have been done in Iran.For this purpose, amongthe18 existing investigative documents in Tehran University, Shahid Beheshti University, Allahmeh Tabatabai University, and Tarbiat Modarres University, a number of 16 met the requirements to be regarded as meta-analysis, which have been done during the last ten years. On this basis, research sample size indicates 8245 people from different walks of life among Iranian people. The findings that stem from the combination of studies probability and reviews over the impact coefficient showed that there is a meaningful relationship between religiousness and trust. This finding confirms the major hypothesis of this research It has been reported in researches there is a direct connection and the average rate of this connection is about 0.4. Also, another hypothesis of this study is the impact of using different statistical tests on the results coming from religiousness and trust. The results proved to be far from sensible. Hence, it shows that using different statistical tests have no influence on the amount of resulted correlation between religiousness and trust.Sample groups’ hypothesis, on the amount of religiousness correlation and trust in the result of variance analysis, did not make any sense, and the hypothesis was eventually refused.Last but not least, the hypothesis of studying field impact on the correlation of religiousness and trust, which was achieved as the result of variance analysis proved to be meaningless. Therefore, it can be concluded that, religiousness, apart from ground factors of research consisting of sample groups, studying field and statistical test using in researches, directly impacts the way people socially trust one another.