A four-strand T type tundish is studied by using water modeling based on similarity principles. A 1∶3 physical model is built to study the influence of different walls, diversion holes and turbulent inhibitors on flow characteristics. The results show that the flow control device of “Y” type baffle+trapezoidal turbulent inhibitor (case F) apparently favor the flow pattern of the tundish. When the flow control device of case F is equipped, the proportion of dead zone goes down from 23.69% to 8.02% which means that the molten steel could mix well; the standard deviation of the average residence time is decreased by 68.85%, which infers that the consistency among all strands is also improved.