Ran Kijram (Thai: ราญ กิจรัมย์; born June 18, 1959), known professionally as Samransak Muangsurin (Thai: สำราญศักดิ์ เมืองสุรินทร์), is a Thai former professional Muay Thai fighter and amateur boxer.

He is a former two-division Lumpinee Stadium champion who was famous in the 1980s and 1990s.

Nicknamed "The Iron Fist, he is often regarded as one of the most fearsome punchers in the history of Muay Thai.

[1] After beating Smaranthong Kiatbanchong by KO in Lumpinee Stadium on 7 April 1992, Samransak announced his retirement from competition.

[2] He since has been working as a Muay Thai trainer in various camps around Thailand and Japan.