According to schiff base reaction, a novel pyrene-o-vanillin Cu(II) fluorescence sensor TM was prepared with pyrene as fluorophore and hydrazine as linker. Its structure was characterized by melting point, 1H NMR, 13CNMR, IR, MS and elemental analysis. Sensor TM had good UV, fluorescence and colorimetric response to Cu(II) in acetonitrile system, and the response time was 12 min. It is not interfered by other metal ions, and can recognize Cu(II) visually and reversibly. The detection limit of TM to Cu(II) was calculated to be 0.48 μmol/L according to the fluorescence titration. Sensor TM had orange solid fluorescence, but its fluorescence in acetonitrile solution was very weak. By comparing the fluorescence intensity after adding water or Cu(II), the aggregation-induced emission (AIE) recognition mechanism of TM was discussed with the aid of UV and fluorescence titration as well as quantum chemical calculation. Sensor TM could be used for detecting Cu(II) in tap water with a recovery of 91.2%~107.3% and relative error of 6.3%~8.8%. High selectivity and rapid response to Cu(II) should make TM as a new AIE-type fluorescence sensor for the detection of Cu (II) in actual samples.