nfluence of flow directions on the gas-liquid two-phase vortex street for triangular column was investigated by experiment. The vorteX emissions of gas-liquid two-phase flow passing by each one of two triangular column with two flow direction(vertically upward & vertically downward) in a tube(inner diameter 50mm) were miasma. An elementary study on the action of gas bubble size upon gas-liquid tow-phase vortex street was also conductal. The resultS illustrate that the influnce of flow direction on the gas-liquid two -phase vortex stud is expressed on the void fraction and the bubble size in the flow.When the bubble she is more then or nearly equal to the vortex emission body she, emission of vortex will be strongly disturbed and the vortex street destroied. In the research, as b/d=0.17, there will be no vortex street for verticaly downward flow.