Jiřina Valenta (born Jiřina Bořilova; October 31, 1940) is a retired Czechoslovak-American wildwater and slalom canoeist who competed from the early 1960s to the early 1970s with then-husband Josef Šedivec under the last name Šedivcová. She won two silver medals at the 1965 ICF Canoe Slalom World Championships in Spittal, earning them in the C2 Mixed and C2 Mixed Team events. She also won a silver medal in the individual C2 Mixed Whitewater Downriver (Classic Race) event and a gold medal in the C2 Mixed Team Whitewater Downriver (Classic Race) event at the 1965 ICF Wildwater Canoeing World Championships, likewise held in Spittal.