Surname Касымджан (Касымджан 
) , in all the world, is an extremely rare cognomen. The surname Касымджан is habitual in Central Asia, particularly Kyrgyzstan, where it is a rare surname. More frequently, Касымджан is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Касымджан | Kyrgyzstan, Kazakhstan, Russia |