To provide a one touch door holder which is beneficial in cost and can be easily attached and extremely easily operated by forming a door member and a vehicle body member with the same shape and quality.

A door holder is attached to a side opening door formed of three sheets of doors and made of a pair of holder member of mutually the same structure. And its horizontal bottom section and the vertical piece crossing at right angles with the horizontal bottom section form a substantially L-shaped shape. Moreover, a curved protrusion projecting outward from the vertical piece is provided at the top of the vertical piece.