The invention discloses a multi-range optical current sensor, belongs to the technical field of optical current measurement, and aims at solving the problems that the current optical current sensor is only applicable to the measurement of large current; the sensitivity and the precision are low when the current optical current sensor is used for measuring small current. According to the multi-range optical current sensor, light beams emitted by a light source pass through a first polarizing film to obtain polarized beams; the polarized beams are subjected to transmission through a semi-transparent semi-reflective mirror to obtain transmission light beams b and reflected light beams a; the light beams a are incident to optical glass with low optical rotation coefficient by a full-reflected mirror; outgoing beams of the light beams a are incident to a light beam selecting part; after being selected, the outgoing beams pass through the full-reflected mirror, the semi-transparent semi-reflective mirror and the polarizing film to obtain polarized beams which are received by a photosurface of a photoelectric detector; the light beams b pass through optical glass with high optical rotation coefficient and then are incident to the light beam selecting part; after being selected, the light beams are incident to the semi-transparent semi-reflective mirror; light beams are obtained by transmission; polarized beams are obtained as the light beams pass through the polarizing film, and the polarized beams are received by the photosurface of the photoelectric detector. The multi-range optical current sensor is used for measuring the optical current.