Abstract: Across-linked polyethylemine with Salicylidene Schiff base-functionalized was achieved via combination quaternarization and aldehyde-amine condensation with 5-Cholromethylsalicylaldehyde as the cross-linking agent and commercial polyethylemine(25 KDa) in methanol at 65℃. 5-Cholromethylsalicylaldehyde with reactive cholromethyl and salicylaldehyde groups could react directly with polyethylemine to afford with optimized the degree of cross-linking density and the amount of Salicylidene Schiff base with the mole ratio of 1:1. Thus, the luminescence properties and form of the obtained cross-linked polyethylemine nanoparticles was investigated by UV-vis spectra(UV-vis), fluorescence spectra(FLL) and dynamic light scattering(DLS).The results showed that after drying to remove methanol the resultant cross-linked polyethylemine could be re-dispersed readily in pure water under ultrasound to obtain luminescent nanoparticles with sizes of ~170 nm by DLS determination and a maximum emission peak around ~500 nm as a result of the aggregation-induced fluorescence enhance. The existence of salicylidene Schiff base linkages(i.e., salicylaldimine ligands) can not only endow the resulting fluorescent nanoparticles pH-controllable in terms of its fluorescence emission and cross-linking structure due to the reversibility of Schiff base linkage in response to pH stimuli, but also endow the resulting fluorescent nanoparticles with a further Zn²⁺-coordinating function to result in a blue shift of a maximum emission peak from ~500 nm to 460 nm, concomitantly a remarkable fluorescence enhancement.