Namsan is a mountain in Seoul, South Korea.

Namsan also may refer to:

• Namsan (Chagang) in Chagang Province, North Korea
• Namsan (Chungju) in Chungju City, North Chungcheong Province, South Korea
• Namsan (Gyeongju) in the heart of Gyeongju National Park, in Gyeongju City, North Gyeongsang Province, South Korea.
• Namsan (Haeju) in Haeju-si, South Hwanghae Province, North Korea
• Namsan (Sangju) in Sangju City, North Gyeongsang Province, South Korea
• Namsan (Unnyul) in Eunyul-gun, South Hwanghae Province, North Korea

• Yeon Namsan (639–701), third son of the Goguryeo military leader and dictator Yeon Gaesomun

• Namsan station (Busan Metro), a station of Busan Metro Line 1 in Busan, South Korea
• Namsanjeong station, a station of Busan Metro Line 3 in Busan, South Korea

• 南山 (disambiguation)
• Nanshan (disambiguation)
• South Mountain (disambiguation)