PURPOSE: To provide a simple matrix drive type liquid crystal display device capable of reducing a driving voltage, display driving a high speed response type liquid crystal display panel without lowering its contract and reducing a driving frequency.

CONSTITUTION: For the simple matrix drive type liquid crystal display panel 10 with J×N rows and M columns, J pieces of functions selected from an orthogonal function series are read out from an orthogonal function memory 1, and the row data are formed by adding the data of a prescribed level to the row except a scanning group based on the functions. and the level of row data are converted to the prescribed level by a row direction driver 9, and are supplied so as to select J rows simultaneously and to drive in time division. On the other hand, the coincidence or noncoincidence between the display data by J rows read out from a frame memory 4 storing the display data of one picture at display timing and the function series of the orthogonal function memory 1 is logically operated, and the operation result is level converted by a row direction driver 8 to be supplied as a column data.