You need a visa for Singapore if you have an Iranian passport
Visa options for Singapore
Electronic visitor visa may be available
Travelers need a visa to visit Singapore for Business or Tourism. A Singapore eVisa is the fastest and easiest way of obtaining a visa for Singapore because travelers can submit their application and supporting documents online. Once the application is approved, travelers receive their eVisa confirmation electronically. Travelers need an eVisa if they arrive in Singapore by air. Travelers can apply for an eVisa through an authorized visa agent, strategic partner, or a local contact in Singapore. A valid visa is required to board the flight. If the visa is expired or doesn’t match the traveler’s passport information, travelers will not be able to board their flight.