The influence of transverse mode were researched with the injection current changing via experiments conducted with 980nm oxide-confined vertical cavity surface emitting lasers (VCSELs). Based on the spatio-temporal rate equation, the injection parameter dependence of the transverse mode characteristics of weak-index guiding VCSELs were theoretically researched by integrating the spatially dependent part. The result of the experiment indicated that the higher-order modes begin to emerge and exhibit strong competition with the injection current increased when the oxidized aperture was kept unchanged, and the distribution of the carrier transfers from the center to the edge. Furthermore, the main order becomes weaker because of the spatial hole burning. Compared with the appearance of higher-order modes with different oxidized aperture, the small injection aperture exhibits better single mode behavior.