A promising photochromic fluorescent chemosensor 1o linked with Schiff base unit was synthesized. It displayed outstanding photochromism and a superb fluorescence turn-on response toward Zn²⁺. Upon the addition of Zn²⁺ to 1o, the fluorescent color of the solution obviously changed from blue to bright green with a 27-fold fluorescent intensity increase. The combination of 1o–Zn²⁺ with 1 : 1 stoichiometry was verified by Job's plot and MS analysis. The detection limit for 1o toward Zn²⁺ was measured to be 8.10 × 10⁻⁸ M. Furthermore, logic gate research was established with Zn²⁺, UV and visible light as input signals and the emission intensity as the output signal.