Surname ทสี (Thasi 
, ทสี 
) , across the world, is a rare family name. The last name ทสี is habitual in Lesotho, where it is quite a common surname, Saudi Arabia, where it is a very rare surname, and South Africa. In absolute terms, it is commonest in Lesotho, Nigeria, and India. Very seldom, ทสี is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thasi | Saudi Arabia, South Africa, Lesotho, Nigeria, India |
| ทสี | Thailand |