Abstract The aim of the present study is to provide an Atlas of IRAN Offshore Renewable Energy Resources (hereafter called ‘the Atlas’) to map out wave and tidal resources at a national scale, extending over the area of the Persian Gulf and Sea of Oman. Such an Atlas can provide necessary tools to identify the areas with greatest resource potential and within reach of present technology development. To estimate available tidal energy resources at the site, a two-dimensional tidally driven hydrodynamic numerical model of Persian Gulf was developed using the hydrodynamic model in the MIKE 21 Flow Model (MIKE 21HD), with validation using tidal elevation measurements and tidal stream diamonds from Admiralty charts. The results of the model were used to produce a time series of the tidal stream velocity over the simulation period. Moreover, to assess the potential of the wave energy in this site, a model was developed based on six-hourly data from a third generation ocean wave model (ISWM-Iranian Sea Wave Model) covering the period 1992–2003. To ensure the information provided to the Atlas is managed and maintained most effectively, all the derived marine resource parameters have been captured in a structured database, within a Geographical Information System (GIS), so enabling effective data management, presentation and interrogation.