A speaker with a hidden folding ring includes a basin frame, a magnetic circuit system mounted on the basin frame, a voice coil disposed in a magnetic gap of the magnetic circuit system and a diaphragm. The diaphragm is of a concave structure, and an outer edge end of the diaphragm is connected to an inner bracket of the basin frame through a folding ring. The folding ring is located below the diaphragm, so that a cavity formed between the folding ring and the basin frame. An inner peripheral end of the diaphragm engaged to the voice coil. The present invention effectively increases the radiation area of the diaphragm, and obtains a higher SPL than the existing speaker of the same size, thereby improving the acoustic performance of the speaker.