Ocean energy, considered as clean energy, is one kind of marine resources of great importance. Its development and utilization have become an indispensable part of national development strategy in China. Testing fields are required when conducting tests of ocean energy generation devices in real sea, which is the key step conducted before engineering prototypes transformed into scale industrialization applications. This paper introduces the construction and operation conditions of large-scale testing fields for wave energy and tidal current energy generation devices and presents a brief comparative analysis. Developing status and related technologies on testing fields for ocean energy power generation in China are also discussed. Furthermore, this paper investigates the necessity of grid-connected test for ocean energy generation and points out that the construction of ocean energy testing fields is helpful to ensure the efficient utilization of ocean energy resources.