Abstract: A valve position indicator for on/off valves includes a card having red and green sectors journalled in a housing, and gravity biased to remain stationary during rotation of the housing about a non-vertical axis. A cover of the housing overlies the card and includes a window through which either the red or green sector is visible. The device may be mounted within a recess of the handle of an on/off valve to indicate correct and incorrect positioning of the valve. The valve is in the correct position when the green sector appears on the window and is incorrectly positioned when the red sector appears in the window. A locking tab projects from the housing and is received within one of two detents of the valve handle to align the window with either the red or green sector, respectively, when the handle is moved to the open position and vice versa.