Endwall film cooling is a significant cooling method to protect the endwall and junction regions of endwall and a turbine vane, where usually a high temperature load exists. This work aims to find the optimized arrangement of film cooling holes on the endwall and improve the film cooling in difficult regions on the endwall, such as pressure side-endwall junction region. Several ideas for film cooling hole arrangement design are proposed, based on the pressure coefficient distribution, streamline distributions and heat transfer coefficient distribution, respectively. Four specified designs are built and compared. The results are obtained by numerical calculations with a well validated turbulence model, the k-? SST model. The designs based on pressure coefficient distributions (Design 1 and Design 2) force the flow from the pressure side to the suction side (SS), especially in Design 2, which adopts compound angle holes. The designs based on pressure coefficients have benefits in the cooling of the suction side but give worse coolant coverage on the pressure side. In addition, Design 1 and Design 2 have little influence on the original pressure field. The design based on streamline distributions (Design 3) has larger coolant coverage on the endwall and provides good coolant coverage on the endwall and pressure side junction region. The design based on heat transfer coefficient distribution provides large overall film cooling effectiveness on both the pressure side and the suction side. More film cooling holes are placed in high temperature regions, which is more effective in practice.