- DTSA stands for Down Town Santa Ana (Santa Ana, CA)
- DTSA stands for Defense Technology Security Administration
- DTSA stands for Discrete-Time Survival Analysis
- DTSA stands for Desk Top Spectrum Analyzer
- DTSA stands for Defense Technical Security Agency (now DTRA)
- DTSA stands for Seaman Apprentice, Dental Technician Striker (Naval Rating)
DTSA