In this paper, a novel hydrazide compound (N'-(1,3 dimethylbutylene)-3-hydroxy-naphthohydrazide) (BMH) was synthesized by a simple three-stage reaction and its chemical structure was confirmed by 1H NMR, 13C NMR and FTIR characterization. This compound was used as fluorescent sensor for the detection of Ni2+ based on photoluminescence quenching. The fluorescence quenching of BMH upon the addition of Ni2+ is due to the formation of coordination complex which was verified by bind model and density functional theory studies. The Ni2+ concentration dependent fluorescence quenching efficiency of BMH was examined and the detection conditions were optimized. There is a good linear relationship between the emission intensity quenching (ΔF = F0–F) and the Ni2+ concentration (c) between 80 nM and 2 μM and the detection limit is 60 nM. The simple preparation of the compound BMH and the high sensitivity of the fluorescent sensor hold great promise for the determination of Ni2+ in environment.