UPR may refer to:
- Popular Republican Union (1919) (French: Union populaire républicaine, UPR) was a Christian democratic party in Alsace, France during the Third Republic. Founded in 1919, the UPR became the dominant party in Alsace during the Interwar era.
- Popular Republican Union (2007) (French: Union populaire républicaine, UPR) is a French political movement created by François Asselineau in 2007 and known for its patriotism and Euroscepticism.
- Ukrainian People's Republic, a short-lived independent Ukrainian state
- Unconditional positive regard, key concept in person-centered psychotherapy
- Undulations per revolution, a tolerancing measure for circularity of a hole.
- Unfolded protein response, a biological response in the endoplasmic reticulum when a large proportion of proteins refuse to fold.
- Unia Polityki Realnej, a political party in Poland
- Union Pacific Railroad, a freight railroad based in Omaha, Nebraska.
- Universal Periodic Review of the United Nations Human Rights Council
- University of Puerto Rico, the public university system of Puerto Rico, or one of its 11 campuses:
- University of Puerto Rico, Medical Sciences Campus
- University of Puerto Rico at Aguadilla
- University of Puerto Rico at Arecibo
- University of Puerto Rico at Bayamón
- University of Puerto Rico at Carolina
- University of Puerto Rico at Cayey
- University of Puerto Rico at Humacao
- University of Puerto Rico at Mayagüez
- University of Puerto Rico at Ponce
- University of Puerto Rico at Rio Piedras
- University of Puerto Rico at Utuado
- Unprocessed Packet Rate, the price of a packed not industrialized product.