Abstract: An auxiliary handlebar of bicycle comprises a main body provided centrally with a spherical connection portion having a connection slot dimensioned to fit securely over one end of the handlebar of a bicycle. The connection portion extends in one direction to form a curved rod having a tapered joint of hollow construction. The connection portion further extends in a direction opposite to the curved rod to form a straight rod. The spherical connection portion provided with a split groove extending to reach the bottom of the connection slot. Located respectively by both upper and lower sides of the split groove are a through hole and a threaded hole engageable with a bolt which can be so tightened as to fasten securely the main body of the auxiliary handlebar with the handlebar of the bicycle. A rotatable rod of the auxiliary handlebar is adjustably fastened to the tapered joint of the main body.