The development of highly selective fluorescent sensors for Zn2+ recognition has received considerable attention due to the vital roles of Zn2+ in physiological and pathological processes.We report herein the synthesis (Scheme 1) and Zn2+ recognition behavior of a new cylen dangled carbazole-based fluorescent sensor L.Sensor L displays ratiometric fluorescence response toward Zn2+ with a high selectivity over other metal ions in aqueous solution (CH3CN/H2O,1:1,v/v,HEPES 10 mM,pH = 7.4) (Figure 1).