The invention relates to a focusable light source structure, which adopts a light guide pipe structure and comprises a luminous body and a condensing mechanism that are arranged on the same optical axis, wherein the distance between the luminous body and the condensing mechanism is continuously adjustable in the focal range at one side of the condensing mechanism. Particularly, the light source structure also comprises an inner sleeve and an outer sleeve which are arranged coaxially; the luminous body is arranged in the outer sleeve; one end of the inner sleeve is inserted into one end of theouter sleeve, and the other end of the inner sleeve is fixedly provided with the condensing mechanism; and the inner sleeve and the outer sleeve can slide relatively. In the focusable light source structure, the illuminance level of the emitted light can be effectively improved, the module test area is enlarged, the uniformity of the emitted light is guaranteed to meet the requirement, and the test accuracy and the optical efficiency are improved, so that the focusable light source structure can become an important structure form for large-area module measurement and simulation of the outer space environment measurement.