Yasin Haji Osman Sharmarke (, ) was a Somali political figure and activist.
Sharmarke was born to the Osman Mahamoud sub-clan of the larger Majeerteen. He was the leader and founder of the Somali Youth League (SYL, established 1943), Somalia's first political party. Having also been instrumental in the organization's creation, Sharmarke and other early SYL nationalists were strongly influenced by the Darawiish of Diiriye Guure and Sayyid Mohammed Abdullah Hassan, emir of Diiriye Guure. Sharmarke died in June 1947.