A laser signal transmission device includes a transparent substrate, a first wavelength light emitting module embedded in the substrate, a first multi-mode optical fiber embedded in the substrate, and a single-mode optical fiber. The first wavelength light emitting module is configured for emitting a first laser signal having a first wavelength. The first multi-mode optical fiber is aligned with the first wavelength light emitting module. One end of the single-mode optical fiber is embedded in the substrate and aligned and optically coupled with the first multi-mode optical fiber, the other end is exposed at the substrate. The first multi-mode optical fiber is arranged between the first wavelength light emitting module and the single-mode optical fiber, and the longitudinal direction of the first multi-mode optical fiber coincides with that of the single-mode optical fiber.