You need to have Iran travel insurance in order to get an Iran visa. Due to the sanctions against Iran, some international companies do not include Iran in their list of countries covered for travel insurance and therefore you need special insurances that cover Iran. But before buying any new insurance, check your current insurance to see if it covers Iran. Terms like “Asia” or “Middle-East” don’t necessarily mean that your insurance covers Iran and you have to make sure by contacting the insurance company.