- DMSI stands for Document Management Solutions, Inc.
- DMSI stands for Désenfumage Maintenance Sécurité Incendie (French fire prevention equipment company)
- DMSI stands for Design Maintenance Systems, Inc. (Canada)
- DMSI stands for Defense Modeling and Simulation Initiative
- DMSI stands for Demethoxysecoisolariciresinol
- DMSI stands for Discount Mortgage Source, Inc. (Rockwall, TX)
- DMSI stands for Direct Marketing Services, Inc (Chicago, IL)
DMSI