The Pioneer Venus observations show a peak in the O\sb2\sp+ concentration at $\sim$170 km altitude in the dayside ionosphere of Venus. In this thesis, the 2-dimensional MHD equations are solved in a self-consistent manner, as an extension to the 1-dimensional model by Cloutier et al. (1987), to present a global model of the Venus dayside ionosphere for solar zenith angles (SZA) ≤ 60\sp∘. The model describes, by calculating vertical profiles at different SZA, ion densities, magnetic field magnitudes, and ion velocities. The model shows that the O\sb2\sp+ peak, at $\sim170kmaltitude,occursthroughoutthedaysideionosphereasobservedbytheOrbiterIonMassSpectrometer(OIMS).Thevelocityfield,whichaffectstheiondistributions,ismainlytangentialneartheionopauseandradialforaltitudesbelow200km.Thedownwardflowaccelerates,near170kmaltitude,duetocollisionalinteractionswiththeneutralatmosphere,andremovestheO\sb2\sp+$ densities to lower altitudes, thus, producing the bump observed in the altitude profile.