LTSA may refer to:

• Local tangent space alignment, a nonlinear dimensionality reduction method
• Land Title and Survey Authority in British Columbia, Canada
• Land Transport Safety Authority, a former government entity in New Zealand, preceding Land Transport New Zealand
• Latin Tropical/Salsa Airplay, a Billboard music chart
• Lyceum Tourism Students Association, of Lyceum of the Philippines University
• Labelled Transition System Analyser, a verification tool for concurrent computer systems
• Long Term Service Agreement, an agreement to provide service over a number of years
• Last Time Seen Alive