Background and objective: Anxiety is defined as an unknown or uncertain factor which causes distress of mind and sense of danger regarding various diseases including heart palpitation. The purpose of this study is to estimate the prevalence of anxiety in Iran through meta-analysis technique. Materials and methods: We searched international online databases such as Scopus, PubMed, ISI and Google Scholar and national online databases such as Magiran, Iranmedex, SID and Medlib for certain standard keywords including prevalence, anxiety, stress and Iran. The data were analyzed using meta-analysis technique (random effects model). Heterogeneity of studies was evaluated by I2 index. The data were analyzed with STATA Ver.11 software. Results: 81 articles were investigated with a sample size of 23455 people from 1993 to 2016. Prevalence of anxiety in Iran was 42% (36% in women and 27% in men). Prevalence of mild, moderate, intense and highly intense anxiety in Iran was 31%, 37%, 19% and 2%, respectively. In addition, the prevalence of depression was 44%, prevalence of stress was 40%, prevalence of overt anxiety was 21% and prevalence of covert anxiety was 24%. Conclusion: Due to the high prevalence of anxiety and as a result stress and depression in the population of Iran, new strategies are necessary to deal with this issue considering different strata and age groups.