Abstract: A bicycle frame assembly is formed of a head tube, a seat tube, a linking member, and a support holder. The linking member includes a first part, two second parts, and two positioning parts. The first part is connected with the seat tube. The two positioning parts are spaced from each other and extend in an interval toward the head tube from the first part to jointly form a limiting portion therebetween. The two second parts are connected with the head tube and located between the head tube and the two positioning parts. The support holder is movably mounted to the limiting portion relative to the linking member for accommodating a portable part or accessory. Therefore, the present invention facilitates that the rider can take or put the portable part or accessory from or into the support holder with his or her natural riding posture.

Abstract: A frame structure for a bicycle includes a head tube, a support tube assembly and a seat tube. The support tube assembly connects the head tube and the seat tube and includes two top tubes, one down tube and two reinforced tubes.