PURPOSE: To obtain a simple and inexpensive solar light collector provided with an automatic tracking function by providing a lens supporting mechanism consisting of a thermally elongatable shape memory alloy in the part below the peripheral of a lens where the light deviating from the optical axis of the lens is received.

CONSTITUTION: A solar light collector consists of a lens 1, a lens holder 2, a solar light collecting part 3, a holding bar 4 for the part 3, a lens supporting mechanism 5 consisting of a thermally elongatable shape memory alloy and a supporting base 6. The solar light enters the part 3 when the incident direction thereof coincides with the optical axis. The light enters the mechanism 5 when the incident direction of the light deviates from the optical axis then heated mechanism 5 elongates and the optical axis of the lens 1 inclines to track the solar light. The mechanism restores the original shape after sunset.