In order to capture the content of an imaged document but avoid the time-consuming full-scale OCR which is frag- ile to handle touching characters, a fast and segmentation- free keyword spotting method is proposed in this paper. The keyword spotting method is based on word shape coding technique. The proposed coding scheme has little ambigu- ity, and can be swiftly executed. It is a promising technique to boost better document image retrieval. The strength of the proposed method is demonstrated in a document filter- ing experiment. The experimental results show that docu- ment filtering based on the proposed method is more than 20 times faster than the one based on OCR, and has com- parable filtering accuracy.