Constantin Doncea (September 26, 1904 – November 4, 1973) was a Romanian communist activist and politician. A railway worker, he played an important part in the Grivița Strike of 1933. Subsequently imprisoned, he escaped and ended up in Moscow. He then joined the International Brigades during the Spanish Civil War. After spending much of World War II in the Soviet Union, he returned to Romania, where he helped establish a Communist regime. Doncea held a series of posts under the new order, but in 1958 he was removed from the party after clashing with its leader Gheorghe Gheorghiu-Dej. In his later years, he was rehabilitated by the latter's successor, Nicolae Ceaușescu.
Doncea was born in Cocu, Argeș County and was a lathe operator by profession. He practiced this work at the Pitești Căile Ferate Române (CFR) state railway deposit and at the Grivița CFR yards in Bucharest. He joined the banned Romanian Communist Party (PCR) in 1931, was a member of the party cell at Grivița and head of the Bucharest rail workers' trade union committee. He belonged to the strike committee during the Grivița Strike of 1933, and in this capacity drew attention for the energy with which he led and instigated the workers. They, his judges and the press all perceived him as the strike leader, while the Comintern created a "Doncea myth" that made him into the most recognizable figure of the Romanian proletariat. Arrested and imprisoned at Jilava and Craiova, he was initially sentenced to hard labor for life by the authorities of the Kingdom of Romania, but his penalty was later commuted to twenty years' hard labor.