The in-cylinder ow eld and the turbulence scale at the ignition timing play an important role in enhancing the propagation speed of the initial ame and the engine combustion. The aim of this work is to investigate the e ect of tumble and swirl ows on the turbulence scale near the top dead centre in a four-valve spark ignition (SI ) engine by an experimental method. In this study, various ow elds such as tumble and swirl ows were generated by intake ow control valves. For investigation of the ow elds, the single-frame particle tracking velocimeter (PTV ) and the twocolour particle image velocimeter (PIV ) techniques were developed to clarify the in-cylinder ow pattern during the intake stroke and the turbulence intensity near the spark plug during the compression stroke respectively. In addition, the ame propagation was visualized by an ICCD camera, and its images were analysed to compare the ow elds. From these experimental results, the e ects of tumble and swirl ows on the turbulence scale and the ame propagation speed were clari ed.