A work light structure according to the present invention comprises: a light source module having a long slender housing laterally and inwardly connected with a printed circuit board so as to partition the housing into a lighting portion and an accommodating portion, the printed circuit board being coupled with a plurality of light emitting diodes (LEDs) arranged in line inside the lighting portion and each of the two ends of the housing is connected with an end cap, respectively, for capping the ends, and one of the end caps is disposed with a power supply device; an extension device disposed in the accommodating portion and formed by connecting at least a resilient component with its two ends onto a connecting rod, respectively, whose external end is inserted through a rod hole at the end cap and is connected with an externally protruding hook; the two hooks are hooked onto two ends of a connecting object to extend the resilient component, such that the power supply device may provide power to the printed circuit hoard to light up the LEDs.