The invention relates to a light source fixing structure and a portable lamp, wherein the light source fixing structure comprises a fixing seat, wherein the fixing seat is connected with a light source fixing end, a vibration absorption elastic sheet is arranged on the fixing seat, is formed by bending and folding an elastic rod and comprises a middle section, a front section and a back section, the front section and the back section are connected with two ends of the middle section, the middle section is provided with a bending and folding part, the bending and folding part tightly presses the upper surface of the light source fixing end, the free ends of the front section and the back section are respectively provided with a hook part capable of being reversely hooked on the fixing seat, and an included angle alpha between one hook part and the corresponding front section or the back section is smaller than 70 degrees. After the light source fixing structure provided by the invention is adopted, the buffer effect can be at least realized in the vertical direction and the horizontal direction, a light source is protected, the vibration absorption elastic sheet can also realize a certain buffer effect on the vibration absorption elastic sheet in other directions, and the all-position protection on the light source is realized. In addition, the light source fixing structure is simple, and the lamp tube mounting and dismounting is convenient.