The invention discloses a condenser lens of an LED (
light emitting diode). The condenser lens is a rotary body in a shape of a circular truncated cone and is provided with an
optical axis which is superposed with a rotary shaft of the rotary body. The condenser lens comprises a
light source containing slot, a light emitting surface and a full reflecting surface, wherein the
light source containing slot corresponds to a small end of the condenser lens, the light emitting surface corresponds to a large end of the condenser lens, the full reflecting surface is positioned on the outer sidewall of the condenser lens, the
light source containing slot is a cylindrical slot, the bottom of the cylindrical slot is provided with an outwards protruded first
conical surface, the middle part of the light emitting surface is sunken inwards so as to form a second
conical surface and an annular surface, the second
conical surface is arranged at the middle part of the light emitting surface and is protruded outwards, the annular surface surrounds the second conical surface, the vertexes of the first conical surface and the second conical surface are arranged on the
optical axis, and the first conical surface and the second conical surface commonly define one central light condensation part. Compared with the prior art, the condenser lens of the LED, disclosed by the invention, has a high-efficiency condensation function on the LED, and emitted light is almost parallel to the
optical axis after light rays emitted by the LED are acted by the condenser lens of the LED; and the condenser lens of the LED can improve the
utilization rate of a lamp on the
luminous flux of the LED.