In accordance with an embodiment, a sheet binding device comprises a sheet shift section (ie a sheet shingling section), a tape attaching section, an information acquisition section and a controller. The sheet shift section shifts a plurality of sheets forming a sheet bundle from each other at an edge of the sheet bundle, so that the sheets are shingled. The tape attaching section attaches a tape (having adhesive) to the edge of the sheet bundle. The information acquisition section, which can be an interface or a sensor, acquires information relating to at least one of the plurality of the sheets, the tape, and a binding method of the sheet bundle by the tape. The controller changes a shift amount between sheets in the plurality of the sheets that is shifted by the sheet shift section based on the information acquired by the information acquisition section.