When he was young, he joined the Tangkas Jakarta badminton club before joining the Indonesian National team PBSI. In 2005 he won the Robot HCMC Vietnam Satellite and the silver medal at the 2005 Southeast Asian Games. His best results on the world circuit until recently were runner-up finishes at the Singapore (2008), Swiss (2007), and Indonesia Super Series (2008) events . He was also a semi-finalist at the Japan Open Super Series (2007) and the Chinese Taipei Open (2007). In September 2008, Santoso won the Chinese Taipei Open after defeating Roslin Hashim from Malaysia in the final round by scores of 21–18, 13–21, 21–10. In October 2009, he won his first Super Series ever in Denmark Open Super Series, after beating Marc Zwiebler of Germany in the final round, 21-14, 21-6. He won gold in the 2009 Southeast Asian Games by defeating Sony Dwi Kuncoro. In 2011, He retained his gold medal in 2011 Southeast Asian Games by beating Tanongsak Saensomboonsuk in 3 sets. In 2012, He helped Indonesia Garuda to win the inaugural Axiata cup 2012. In June 2012, he won Indonesia Open Super Series premier badminton title 21-18, 13-21, 21-11 after defeating Du Pengyu of China in the final.