This systematic review aimed to provide an updated estimate on the prevalence of human immunodeficiency virus (HIV) infection among non-injecting people who use drugs (PWUD) and the various subgroups and the odds of HIV infection in the injecting compared to non-injecting PWUD. A comprehensive search of international, regional and national databases was performed from January 2005 to May 2020. We conducted backward citation tracking of the included studies and contacted experts for unpublished studies. Studies providing HIV prevalence among non-injecting PWUD were included. Data were also drawn from a previous systematic review, covering 10 years from 1998 to 2007, and was added to the new database. The HIV prevalence was pooled for non-injecting PWUD and other subgroups using the random-effects model. Seventeen studies with a total sample of 9912 non-injecting PWUD were found. The prevalence of HIV infection was 1.9% (95% confidence interval 0.9, 3.1) for 2007 and afterward (nine studies). It was not significantly different from the estimate for the years before 2007 (0.5%; 95% confidence interval 0.0, 2.0; eight studies). No significant difference was found among gender subgroups. The overall estimate of odds of HIV infection among injecting PWUD was 5.7 (95% confidence interval 3.2, 10.0) times higher than non-injecting PWUD. The HIV prevalence among the non-injecting PWUD was higher than the general population in Iran. Targeting non-injection PWUD by preventive measures such as harm reduction, drug and psychoeducation, and surveillance seem to be crucial in reducing HIV prevalence in this group.