This paper presents a method that using inner transverse prestressing bars to enhance the shear capacity of concrete beams, which can be used in new transformer beams to decrease the sectional dimensions. Four transversely prestressed concrete beams and one ordinary reinforced concrete beam were tested. The nonlinear finite element method was applied to analyze them, parametric study was carried out to analyze the behavior of transversely prestressed concrete beam, and the following conclusions can be drawn: (a) With the increase of the prestressing force level, the shear capacity of transversely prestressed concrete beam increase rapidly, which means that prestressing force level has a significant effect to the shear capacity of transversely prestressed concrete beam. (b) If the area of transversely prestressing bars is almost same, the transverse bars with smaller diameter and smaller spacing can enhance shear capacity of transversely prestressed concrete beam more efficiently. (c) If steel plate of 100 mm×350 mm×16 mm being changed to steel padding of 100mm×100mm×16 mm the shear capacity of transversely prestressed concrete beam will decrease little. It means in the actual engineering the steel plate can be changed to steel padding, and then the amount of steel will be reduced.