A furan‐based water soluble fluorescent probe (E)‐N′‐(2,4‐dihydroxybenzylidene)furan‐2‐carbohydrazide (DBF) has been synthesized and characterized by 1H NMR, 13C NMR, ESI‐mass spectroscopy and single crystal X‐ray diffraction techniques. The synthesized probe exhibits a “turn‐on” fluorescence response towards Al3+ in Tris‐HCl buffer (10 mM) with no significant interference from other metal ions. The strong fluorescence in the presence of Al3+ is attributed to the CHEF (chelation enhanced fluorescence), inhibition of PET (photo‐induced electron transfer) and C=N isomerization. 1 : 1 stoichiometric ratio between DBF and Al3+ was rationalized by Job's plot. Binding constant and LOD were calculated to be 1.031×105 M−1 and 6.34×10−8 M, respectively. MTT assay on live A549 cells indicated no serious cytotoxicity in the cells even at higher concentration. Further, DBF was successfully used for the detection of accumulated Al3+ in the cytoplasm of cells.