We experimentally realize a kind of entanglement transformations of bipartite pure states with 100% efficiency. The protocol employs two-outcome positive operator-valued measures (POVMs) and can transform two-photon maximally entangled state to any two-photon entangled pure state with 100% efficiency. The average fidelity of all output states is 96%. Moreover, the scheme to implement arbitrary POVM on single-photon polarization state is also discussed. In principle, our setup can be applied to any kind of entanglement transformations of two-qubit entangled states to achieve optimal successful probability.