The invention discloses a side entering type LED panel lamp without a light guide plate. The side entering type LED panel lamp without the light guide plate comprises an LED light source array which is provided with a radiator, a light projector array, an optical cavity, a backboard and a cylindrical microlens array sheet, wherein the light projector array is connected to the front of the LED light source array which is provided with the radiator; light rays emitted by the light projector array are mixed in the optical cavity; the backboard is arranged at the back of the optical cavity in a matching manner, and the cylindrical microlens array sheet is arranged at the front end of the optical cavity in the matching manner; an optical axis of each light projector is obliquely arranged by 5-10 degrees relative to the optical cavity surface; the light rays which are emitted by LED light sources and passing through the upper side edge of the aperture of each light projector are projected to the right side edge of the optical cavity along A, B and C routes; the light rays passing through the lower side edge of the aperture of each light projector are projected to the left side of the optical cavity along a D route after passing through each light projector; the light projectors are symmetrically positioned according to a symmetric axis of the optical cavity. Therefore, the light rays at the upper and lower aperture side edges of the light projectors at two sides can be mixed; the light projectors are divided into two parts along the symmetric axis, the curve parameters of the two parts are different, and thus light ways on the lower surface of the optical cavity can be uniformly mixed.