Family name คำเพ็ญ (Pen 
, Khampen 
, Khamphen 
) , in the entire world, is a common last name. The cognomen คำเพ็ญ is habitual in Malaysia, where it is quite a rare surname, Netherlands, and Malta. Measured by absolute frequency, this name is the most popular in Malaysia, China, and Indonesia. Likewise, คำเพ็ญ is the forename as well as the last name.