A high-energy and simple structure switchable dual-wavelength lamp-pumped Nd:YAG MOPA laser system is introduced. A simple and robust method that improves the conversion efficiency of the second harmonic of a Nd:YAG MOPA laser system is reported, as a demonstration of the concept, through engineering a beam profile with uniform intensity distribution via glass soft-edge diaphragm. With the proposed scheme, an MOPA laser system at 487 ps pulse width and 10 Hz repetition rate with the pulse energy of 702 mJ at 1064 nm and 433 mJ at 532 nm among the switchable dual-wavelength amplifier is demonstrated. Our work provides a promising approach for achieving high energy and uniform intensity distribution Nd:YAG MOPA laser system that can be readily used in the field of medical aesthetics.