A newly developed acylhydrazone derivative (compound 1 ) displayed solvatochromic fluorescence effect with dominant fluorescence from its keto form in most solvents, fluorescence from its phenolic anion in DMF, and concentration-dependent emission intensities for both enol and keto forms in toluene. The aggregation-induced emission enhancement (AIEE) properties of 1 were observed in THF − H 2 O and DMF − H 2 O. Red fluorescence in the root cells of paulownia sprouts was observed for application of 1 as a fluorescence marker. Notably, strong fluorescence centered at 602 nm with a large stokes shift (232 nm) and an absolute quantum yield of 22% for 1 was obtained in crystals. X -ray analysis indicates that the fluorescence of crystal 1 is caused by intramolecular hydrogen bonding-induced limitation in C  =  N isomerization and weak intermolecular interactions. Furthermore, compound 1 exhibited good colorimetric/ratiometric sensing properties for quantitative detection of acetate and dihydrogen phosphate anions with detection limits of 250 nM and 170 nM, respectively, and blue-shifted amplified fluorescence response with detection limits of 45 nM and 62 nM, respectively. Based on 1 H NMR analyses, intermolecular hydrogen bonding/deprotonation interactions of 1 with these anions and inhibiting ESIPT process were proposed for anions sensing.