Incised stones have been reported from locations across Idaho, most commonly in the panhandle region. Though relatively rare, they are in some instances associated with Late Archaic (2000--150 B.P.) period sites and in southeastern Idaho with the Fremont pattern (1300--500 B.P.). Four types of incised stones are described. Type 1 items consist of stones characterized by parallel lines located on the face or margins of the stone with lines that may be horizontal, vertical or diagonal, or a combination, though one direction is usually predominant; in some cases, the lines are minimal in length and/or number. Type 2 incised stones are characterized by centrally placed hachure, while Type 3 stones are characterized by etching or by lines that are irregular and multi-directional in placement and without discernible patterning. Type 4 stones are more decorative; these display combinations of motifs, including zig-zags, ladders, parallel lines, and chevrons. The geographic and temporal distributions of incised stones in Idaho are reviewed, accompanied by observations regarding their function.