The invention provides an optical-fiber-free handheld raman spectrometer based on free transmission in light space. A spectrometer accommodating cavity, an optical-fiber-free probe accommodating cavity and a laser cavity are formed in a shell body, an optical grating device, a light detection device, a lens, a focusing lens and a control circuit board are installed in the spectrometer accommodating cavity, and a coupling lens device, a probe focusing lens and a light splitting structure are installed in the optical-fiber-free probe accommodating cavity; a laser is installed in the laser cavity, the spectrometer accommodating cavity is adjacent to the probe accommodating cavity, and a slit used for guiding light is formed between the spectrometer accommodating cavity and the optical-fiber-free probe accommodating cavity; a sample testing accessory installing port is formed in the side, away from the slit, of the optical-fiber-free probe accommodating cavity, a sample testing accessory is installed in the sample testing accessory installing port, the coupling lens device, the light splitting structure, the probe focusing lens and the sample testing accessory are successively connected, and the end, away from the light splitting structure, of the coupling lens device is connected with the slit. The raman spectrometer has the advantages that there is no optical fiber, a detecting signal is strong, and the size of the spectrometer is small.