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Vortex shedding and aerodynamic forces on a circular cylinder in linear shear flows with its axis normal to the plane of the velocity shear profile at subcritical Reynolds number are investigated. The shear parameter β, which is based on the velocity gradient, cylinder diameter and upstream mean velocity at the center plane of the cylinder, varies from 0 to 0.27. The Strouhal number has no significant variation with shear parameter. The time-mean base pressure increases and the fluctuating component of base pressure decreases significantly with increase in shear parameter. Vortex shedding is suppressed by the velocity shear. Dislocation of the stagnation point takes place and this influences the pressure distribution around the cylinder together with the velocity shear. Mean lift force occurs in the shear flow due to asymmetry of the pressure distribution, and it acts from the high velocity side to the low velocity side. In addition, the lift coefficient increases and the drag coefficient decreases with increase in shear parameter.