Abstract: An umbrella supporting device for detachably supporting an umbrella substantially in an upright position at the center of the handlebar of a bicycle. A supporting post is removably attached substantially in an upright position to the stem of the handlebar of the bicycle. The supporting post is divided into upper and lower post members, the former of which is telescopically received and locked in position in the latter. A clamping mechanism is attached to the upper end of the upper post member so as to detachably clamp the handle of the umbrella. The clamping mechanism has a pair of clamping members, the inner sides of which face each other so as to hold inbetween the umbrella handle. An operating lever or bar is used to bring, when manually operated, one of the clamping members toward the other for the clamping purpose.