tBoth active and reactive power play important roles in power system transmission and distribution net-works. While active power does the useful work, reactive power supports the voltage that necessitatescontrol from system reliability aspect as deviation of voltage from nominal range may lead to inadvertentoperation and premature failure of system components. Reactive power flow must also be controlled inthe system to maximize the amount of real power that can be transferred across the power transmit-ting media. This paper proposes an approach to simultaneously minimize the real power loss and thenet reactive power flow in the system when reinforced with distributed generators (DGs) and shuntcapacitors (SCs). With the suggested method, the system performance, reliability and loading capacitycan be increased by reduction of losses. A multiobjective evolutionary algorithm based on decomposi-tion (MOEA/D) is adopted to select optimal sizes and locations of DGs and SCs in large scale distributionnetworks with objectives being minimizing system real and reactive power losses. MOEA/D is the pro-cess of decomposition of a multiobjective optimization problem into a number of scalar optimizationsubproblems and optimizing those concurrently. Case studies with standard IEEE 33-bus, 69-bus, 119-bus distribution networks and a practical 83-bus distribution network are performed. Output results ofMOEA/D method are compared with similar past studies and notable improvement is observed.