This paper describes an experimental study on behavior of steel and high-strengrth concrete (HSC) composite beams. Seven model HSC composite beams and one normal. strength concrete (NSC) beam were tested under monotonic loading. All beams were designed for a full shear connection between the steel beam and the concrete flange USing shear studs. It was identified that the HSC composite beams had higher initial stiffness and very distinct post. yielding characteristics compared wim the NSC beam. Test results of the HSC specimens also showed several favorabte design aspects such as a larger margin beyond the steel yielding and greater ultimate deformability. Analysis based on the current design codes can providea reasonable estimation to the flerural bzitial stiffness andul timate flexural capaci of the HSC composite beams.