A head pipe of a vehicle body frame includes an upper side head pipe with a pair of upper and lower facing piece parts extending from an upper side pipe part so as to fit to upper and lower wall portions of a pair of right and left main frames, a lower side head pipe with a lower side pipe part joined to the upper side pipe part and a front side tongue piece part extending from the lower side pipe part so as to fit to a front wall portion of a down frame, and a reinforcing member joined to a rear portion of the upper side head pipe and having a rear side tongue piece part extending so as to fit to a rear wall portion of the down frame from a vertical wall part positioned between inner side wall portions of the main frames.