The transmission through one-dimensional photonic crystal with negative refractive index defects was studied by using transfer matrix method.Quarter-wave stack photonic crystal of 19 periods with three negative refractive index defects were taken as an example for numerical calculation.It is found that when the refractive index of defect was changed,the coupling effect between the defect modes was varied,which results in the change of the impurity band.Some sharp transmission peaks apper in the forbidden band when the refractive index of defects is appropriate.It is different from the the impurity band formed by positive refractive index defects.