Wavelength detectors are optoelectronic devices distinguishing the wavelength of incident light and have been used for applications including safety detection and biomedicine. Nowadays, wavelength detectors are developed to realize small size, high performance, and feasible integration. In this paper, a single-pixel wavelength detector was fabricated based on an integration of a graphene-silicon-graphene detector on a nanograting metasurface, in which two nanopillar metasurface filters were printed on symmetrically reversed graphene-silicon Schottky junctions using two-photon femtosecond laser printing technology. The transmittance of the two nanopillar filters was tuned under different incident wavelengths, resulting in different optical responses of the Schottky junctions. The incident wavelength could be detected by measuring the photocurrent and dark current of the device under different bias voltages. The results demonstrated that the wavelength detector could detect visible light with wavelengths rang of 450 nm to 700 nm, with a responsivity of 0.19 μA/W at a bias voltage of 0.1 V and a response speed of less than 1 ms, and the resolution was about 14.1 nm. The device exhibits the advantages of high integration and single-pixel detection, providing an innovative pathway toward high-density on-chip integration of multifunctional detectors.