FSSP

FSSP may refer to:

• Priestly Fraternity of Saint Peter, a traditionalist Catholic society of apostolic life for priests and seminarians that is in communion with the Holy See.

• Families of structurally similar proteins, a protein structures database
• Federal Bailiffs Service (Russia), abbreviated FSSP in Russian
• Firing squad synchronization problem, a problem in computer science and cellular automata
• Frances Slocum State Park, a state park in Luzerne County, Pennsylvania
• Priestly Fraternity of Saint Peter, a society of traditionalist Catholic priests and seminarians
• Fresh Start Schools Programme, a programme for schools in South Africa
• Forward Scattering Spectrometer Probe, a class of optical instruments designed to measure size and concentration of particles suspended in the air (such as cloud droplets)