The randomness of material property and component dimension has significant influence on the overstrength factor of partially-restrained steel frame with RC infill walls (PSFRCW). The Latin-hyper cubic sampling approach was adopted to take into account the randomness of material property and component dimension, including mechanical property of steel, steel bar and concrete, thickness of RC infill wall, rotation stiffness and bending bearing capacity of partially-restrained connection. A total of 160 PSFRCW specimens with four groups were designed according to the GB 50011-2010'Code for seismic design of buildings', and the effect of story number and seismic precautionary intensity were also considered. The capacity curves of 160 PSFRCW structures were developed by pushover analysis under the two lateral loading distribution modes, i.e., uniform lateral loading distribution and generalized power loading distribution modes. The analytical results show that the overstrength factor of PSFRCW considering material property and component dimension randomness is 15% larger than the nominal values of PSFRCW structure. The overstrength factor determined by generalized power loading distribution mode, which considered the effect of higher modes, is less than the overstrength factor values from uniform lateral loading distribution mode. At the same seismic precautionary intensity, the overstrength factor of PSFRCW takes on the increasing tendency with the increase of story number. With the same story number, the overstrength factor of PSFRCW exhibits the decreasing tendency with the increase of seismic precautionary intensity. The suggested overstrength factor of PSFRCW is 3.5 and 3.2 for seismic zone 8 and 9, respectively. [ABSTRACT FROM AUTHOR]