An embodiment relates to a speaker and a speaker module. The speaker comprises a vibration system and a magnetic circuit system; the vibration system comprises a diaphragm and a voice coil coupled to the diaphragm; a space between a front side of the diaphragm and a front sound cavity cover forms a front sound cavity, and a space between a back side of the diaphragm and a rear sound cavity cover forms a rear sound cavity; wherein the speaker further comprises a plurality of injection molding inserts disposed along a vibration direction of the diaphragm, and the injection molding insert comprises a first end and a second end; the first end is joined with a surface of the front sound cavity cover close to the diaphragm, and the second end is joined with a surface of the rear sound cavity cover close to the diaphragm. One technical problem to be solved by the embodiment of the present invention is to ensure, by using the injection molding inserts, the stability of relative distance and parallelism of the diaphragm connection surface of the housing with respect to both the front sound cavity support surface and the rear sound cavity support surface, so as to ensure stability of the acoustic performance of the speaker.