Being a new entry point of the researches on independent directors, the heterogeneity of independent directors professional background can bring forth more resources for the banks decision making, the heterogeneity of the number of part time independent directors can lead to the higher supervision efficiency for the board of directors, and the heterogeneity of the genders can produce different effects for the bank management. All the above have a significantly positive effect on bank performance, while the heterogeneity of independent directors tenure has a significantly negative effect on bank performance.