RSM may refer to:
- Removable Storage Manager, a Windows program to manage removable-media storage systems.
- RSM File Extension for a Delphi Remote Debugging Symbols file.
- Resource Standard Metrics, a source code metrics and quality analysis tool for Windows, Linux and Unix.
- RSM International, a worldwide network of professional services firms providing tax, accounting, consulting, and specialist advisory services
- RSM McGladrey, a tax, accounting and consulting firm based in Bloomington, Minnesota, USA
- R. Stevie Moore, an American singer-songwriter
- Rajah Solaiman Movement, a Filipino Islamic organisation, reputed to be armed
- Rancho Santa Margarita, California, a city in California, USA
- Regimental Sergeant Major, a warrant officer appointment in the British and most Commonwealth armies and the Royal Marines
- Religious Order of the Sisters of Mercy, an order of Catholic women
- RSM - Remote Site Management, an electronic reporting system (as example, RSM for radio repeater systems)
- Renault Samsung Motors, a South Korean motor manufacturer
- Republic of San Marino (ISO country code)
- Response surface methodology, sequential experimentation for improvement and for finding an optimal response
- Reynolds stress model, for modeling turbulence in fluid dynamics
- Rotterdam School of Management (RSM Erasmus University), the business school of Erasmus University, Rotterdam, Netherlands
- Route Switch Module, a component of a powered device that provides network routing services
- Rover Scout Master, a Rover Scout Leader
- Royal Saskatchewan Museum, a museum in Regina, Saskatchewan, Canada
- Royal School of Mines, an institute of higher education in London, England
- Royal Society of Medicine, a British medical society
- Russian School of Mathematics, an after-school mathematical education program based in Massachusetts, USA
- Radioamaterski Sojuz na Makedonija, an amateur radio organization in the Republic of Macedonia
- RS Media, another product in WowWee's line of biomorphic robots, based on a walking system designed by Mark Tilden
- Reliable Source Music, an independent production music company