To study the influence of integral scale on buffeting response of long-span bridge which cannot be taken into account in the passive turbulence wind tunnel test and to provide a reasonable evaluation of wind tunnel test result, taking a typical cable-stay bridge and a suspension bridge as samples and combining aerodynamic parameters of the section model in wind-tunnel test, the influence of turbulence integral scale and wind spectra on buffeting responses were studied in frequency domain. The results show that buffeting responses decrease with increase of integral scale at lower wind speed; while at higher wind speed, buffeting responses increase first and then decrease. After comparing the integral scales in wind tunnel test and in wind standard, the result shows that buffeting response in wind tunnel were overestimated at lower wind speed, but underestimated at higher wind speed. After comparing the influences of several frequently-adopted horizontal and vertical wind spectra on buffeting response, the result shows that the influence of different horizontal wind spectra can be neglected, but the influence of different vertical wind spectra should be taken into account.