The invention discloses a solid weighing system with adjustable volume. The solid weighing system comprises a weighing cavity, wherein the volume is adjusted through an adjusting knob, the adjusting knob is connected to the bottom of the weighing cavity, and meanwhile, a volume display window is arranged; a floating scraper is arranged, the scraper is arranged at the front end of the weighing cavity, a flat push rod is arranged at a handle position, a spring is arranged in the rod, the scraper is horizontally pushed after weighing, and the weighing accuracy is guaranteed. The system has the beneficial effects that a solid weighing device with the adjustable volume is time-saving and labor-saving, the waste is not caused during weighing, the cost is reduced, the time of workers is effectively saved, the production efficiency is improved, and the amount of the weighing samples can be adjusted according to own requirements.