Using a systematic review of all available studies between 1991 and 2011, the prevalence of food insecurity in the Islamic Republic of Iran was estimated. After document evaluation and data aggregation, studies were analysed in separate categories based on the methods used dietary recall, household income/expenditure or experiential/ perception-based surveys. Meta-analysis of dietary-recall studies showed small non-significant increases between 1994 and 2004 in the prevalence of mild (from 8.8% to 9.3%) and moderate food insecurity (from 5.4% to 5.6%). Severe food insecurity was 3.8% and 3.7% in 1994 and 2004 respectively. Prevalence of food insecurity (moderate to severe) based on household income/expenditure surveys was consistently reported to be 10%. A separate meta-analysis of experiential/perception-based studies revealed rates of mild, moderate and severe food insecurity of 28.6%, 14.9% and 6.0% respectively. By combining study results in this manner makes it possible to come up with more realistic estimates for evidence-informed policy-making, until development of a national food insecurity surveillance system.