A series of numerical simulations were performed to investigate the effects of geometric parameters on cooling performance of a laminate porous plate with a sparse hole array, under a given coolant massflow rate per unit wall-surface area and the combustor linear representative conditions. The relationship between impinging-hole number, pin-fin and film-holes number is 1∶10∶1. Among the current ranges of geometric parameters, it is found that the film-hole diameter and impinging-hole diameter have relatively stronger influence on overall cooling effectiveness and pressure drop across the laminate porous plate. Increasing film-hole diameter is helpful for improving overall cooling effectiveness and reducing pressure drop. Increasing film-hole diameter results a reduction of pressure drop and overall cooling effectiveness. The variation of pin-fin diameter or impinging distance has nearly no influence on the pressure drop. The increase of pin-fin diameter results in a little increase of overall cooling effectiveness. Small dimensionless impinging distances seems to be a little advantageous.