A light distribution lens, having a saddle-shaped upper surface consisting of multiple segments of connected smooth curved surfaces and forming a non-smooth curved surface, and an non-smooth curved surface is formed between two neighboring smooth curved surfaces in the multiple segments of the smooth curved surfaces; a recess is provided in the center of the bottom of the light distribution lens for placing an LED light source. Also disclosed are a light distribution lens module having the light distribution lens, and an LED energy-saving lamp. The light distribution lens improves uniformity of emergent speckles, improving illumination effect, and thus is capable of being widely used in the lighting industry.