Disclosed herein is a detachable door hinge device for a vehicle. The door hinge device includes a first hinge portion protruded from a door bracket and having a hole for pivot connection formed inside thereof. A pivot pin is rotatably inserted into the hole for pivot connection. A latching groove is formed along the outer circumference of an intermediate region of the pivot pin. A second hinge portion is formed in a body bracket and has a pivot pin hole formed therein for inserting the latching groove region of the pivot pin thereto. The pivot pin hole has a serration formed so as to fit to the serrated portion. A control pin hole is formed in the second hinge portion perpendicularly to the pivot pin hole. A control pin is inserted rotatably into the control pin hole in order to control an axial movement of the pivot pin.