Abstract: By using a method for estimating extreme value of non-Gaussian wind pressure proposed by the authors, the wind pressure measurement wind tunnel test data in the aerodynamic database for low-rise buildings in Tokyo Polytechnic University in Japan are processed and the effects of geometrical parameters on the most unfavorable negative wind pressure coefficients on the gable roof of low-rise buildings are studied. Some new and detailed conclusions are drawn from the results. The roof pitch has great effects on the values and locations of the most unfavorable wind pressure coefficients of gable roofs. The aspect ratio of building has smaller effects on the most unfavorable wind pressure coefficients. In most cases, the most unfavorable wind pressure coefficients increases slightly with the increase of the aspect ratio. The side ratio has less influence on the values and furthermore the influence regularity is weak.