A defeat detection method for quill using the finite ridgelet transform is mentioned. This method reduce the average gray values of quill and analytic statistics methods are used in ridgelet transform according to points of quill. After ridgelet transform the linear singularity is further highlighted and the quantization errors caused by cutting image of quill is overcomed. With this method the differences between background and quill are eliminated too and automaticly adjusting the sub-image size for transformation according to the width of quill is realized. The experiment results show that this method can effectively detect smaller linear defects and hence satisfy the industrial production needs.