Abstract: The present invention relates to laser leveling device suitable for construction. The present invention uses a standard low cost laser diode module as the laser source and optical system. A novel method is provided to align the non-collimated beam emitted from the standard low cost laser diode module so that it is perpendicular to the rotational axis of the laser level. The present invention describes a laser level which can be operated in four different modes: dot mode, line mode, oscillation mode and plane mode. Dot mode provides two level laser dots. Line mode provides a short bright level line. Oscillation mode provides a long bright reference line. Plane mode provides a level 360 degree reference plane. The invention also provides a structure which allows two vertical reference planes which are perpendicular to each other and perpendicular to the horizontal reference plane to be generated.