The Sub-degree of Royal Government of Cambodia No. 07 dated 09 January 2009 upgraded Sihanoukville into a Province. Preah Sihanouk Province border Koh Kong Province to the south, Kampot Province and Kampong Speu to the east and the gulf of Thailand to the south and west.

The Province of Preah Sihanouk, formally Kampong Som, is the only deep–water port of Cambodia. 

The Province of Preah Sihanouk is a relatively new destination and is designated as one of the three poles economic development areas, Preah Sihanouk, Siem Reap, and Phnom Penhand it is the only one province has been transformed a Multi-purpose Special Economic Zone in the country by the Royal Government of Cambodia. It is the site of country’s only deep seawater port, serving as a commercial get way to local and international trade. The Coast Province of Preah Sihanouk is a member of the Club of the Most Beautiful Bays in the World in recognition of its stunning 175. 81km of coastline, 32 islands and rich natural resources that provided significant livelihood opportunities in fishery production, trade services, industrial tourism and eco-tourism. The Province is located in the center of ASEAN, thus very accessible page- by road, rail route, air and sea and it is blessed with no serious natural disasters, such as storm, earthquake, tsunami, flooding or landslide.