A power generating system being disposed, in use, in a flow field, wherein streams of the flow field flow along a main fluid flow direction, the power generating system comprises: a supporting device, including at least one supporting body having a stream-facing region, a side-stream region, and a vortex region, wherein the stream-facing region is defined as a surface facing the streams flowing along the main fluid flow direction, the side-stream region is defined as a surface lateral to the streams flowing along the main fluid flow direction, and the vortex region is defined as a surface facing away from the streams flowing along the main fluid flow direction; a down flow is formed in the stream-facing region when the streams flow through the supporting body and contact the stream-facing region; a lateral flow is formed in the side-stream region when the streams flow through the side-stream region, and a vortex flow is formed in the vortex region; a power generating device being disposed on the supporting device, the power generating device comprising a plurality of power generating units (31, 32, or 33), wherein the power generating units (31, 32, or 33) are disposed on the stream-facing region, the side-stream region, and on the vortex region; and a diversion trench formed on the side-stream region for the power generating units on the side-stream region disposed therein, the diversion trench diverting the streams into the lateral flow and guiding the lateral flow to drive the power generating units; wherein the power generating unit (31, 32, or 33) is selected from a group consisting of a turbine generator and a vibration generator, and at least one of the power generating units disposed on the stream-facing region is driven to generate power by the down flow. a supporting device, including at least one supporting body having a stream-facing region, a side-stream region, and a vortex region, wherein the stream-facing region is defined as a surface facing the streams flowing along the main fluid flow direction, the side-stream region is defined as a surface lateral to the streams flowing along the main fluid flow direction, and the vortex region is defined as a surface facing away from the streams flowing along the main fluid flow direction; a down flow is formed in the stream-facing region when the streams flow through the supporting body and contact the stream-facing region; a lateral flow is formed in the side-stream region when the streams flow through the side-stream region, and a vortex flow is formed in the vortex region; a power generating device being disposed on the supporting device, the power generating device comprising a plurality of power generating units (31, 32, or 33), wherein the power generating units (31, 32, or 33) are disposed on the stream-facing region, the side-stream region, and on the vortex region; and a diversion trench formed on the side-stream region for the power generating units on the side-stream region disposed therein, the diversion trench diverting the streams into the lateral flow and guiding the lateral flow to drive the power generating units; wherein the power generating unit (31, 32, or 33) is selected from a group consisting of a turbine generator and a vibration generator, and at least one of the power generating units disposed on the stream-facing region is driven to generate power by the down flow.