Last name เพ็ญแก้ว (Penkaew 
, เพ็ญแก้ว, Penkaewn ) , in the entire world, is a very rare cognomen. The last name เพ็ญแก้ว is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname. Much less frequently, เพ็ญแก้ว is the forename as well as the last name.