This paper reviews DGs’ locating and sizing methods applied in micro-grids and in distribution network, and compares them in the above two applications. Firstly, comparison of physical characteristics including topology and outside port to grid, and operation modes including all kinds of modes before and after faults, is carried out between the micro-grids and distribution network. According to the fore-mentioned comparison, the similarities are found, and then the analysis and comparison of DGs’ sizing and locating problems are implemented deeply as follows. Following problems are pointed out:firstly, the economic or/and reliability objectives are commonly selected, while the difference of the practical applications in specific situations will result in the final different schemes. Secondly, the comparison in the direct and indirect connections of DGs is carried out deeply according to the optimal objectives, operation modes, the access of distributed storage units, et al. Finally, besides the above difference points, three aspects concerning the reachable degree of the assigned objective, the meticulous modeling on certain equipments connected into grid, the regulative capability of grid consisting of some topology adjusting equipments and power quality improvement equipments, are discussed further to help the practical engineering. This work is supported by National Natural Science Foundation of China (No. 51577086), Opening Fund of Jiangsu Distribution Network Collaborative I nnovation Center (No. XTCX201606), Scientific Research Fund of Nanjing Institute of Technology (No. CKJA201406), and Jiangsu Provincial Prospective Joint Research Foundation for Industry-University- Research, China (No. BY2015009-03).