Rangsiroj Panpeng or Ek Rangsiroj (Thai: รังสิโรจน์ พันธุ์เพ็ง, เอก รังสิโรจน์; born: September 13, 1974 in Amphoe Bang Ban, Ayutthaya Province) is a Thai actor under Channel 7.

Rangsiroj was born in a poor family in Ayutthaya Province.

During his time as a temple boy, he acts like the other temple boys, such as served the monks while alms-round in the early morning etc., until he graduated at the age of 22–23.

He is often role as manly character, has frequently starred in the dramas of Chalong Pakdeevijit, as well as in Angkor 2, Thong 9, Sao 5, Suea Sung Fah.

In addition, he is also a songwriter, including singing for dramas on Channel 7.