No reason was given for the rift.
Cuoco, 29, married the 28-year-old, professional tennis player Dec. 31, 2013 after a brief courtship. They have no children.
"Kaley Cuoco and Ryan Sweeting have mutually decided to end their marriage," Cuoco's representative told People magazine Friday. "They ask for privacy at this time. No further statement will be issued regarding this matter."
The actress is also known for her work in the sitcom 8 Simple Rules.
She dated her BBT co-star Johnny Galecki for several years before marrying Sweeting in a fire and ice-themed ceremony. Cuoco and Galecki's characters -- Penny and Leonard -- got married on the show this week.