Three carbothioamide derivatives with reversible P-type photochromic properties in the solid state were synthesized in a one-step reaction. Based on the single crystal structures, the FT-IR spectra and theory calculations, the proposed photochromic mechanism was the intermolecular proton transfer between the thio-keto and thioenol tautomer. Nanofibrous membranes were prepared by electrospinning, which showed improved reversible photochromic properties in comparison of the compound itself. This work may open a new pathway for design and synthesis of the new solid-state photochromic materials with high-performance.