Yuri Alekseyevich Gagarin (Russian: Юрий Алексеевич Гагарин; 9 March 1934 – 27 March 1968) ek Russian cosmonaut (astronaut) rahaa. Uu pahila insaan rahaa jon ki space me gais rahaa, 12 April 1961 ke, ek rocket jiske Russia chhorris rahaa.