Herein, a novel fluorescein-based fluorescent probe FHP was systematically designed and synthesised, which exhibited aggregation-induced emission enhancement (AIEE) properties. FHP showed the maximum emission response at a wavelength ( ) of 516 nm. Using probe FHP, convenient and cost-effective sensing of Fe in solution and solid states was accomplished with notable sensitivity and selectivity. Quenching of the FHP fluorescence intensity was observed owing to the chelation between the electron-rich probe and electron-deficient Fe, with a detection limit of 253 nM. The FHP-Fe interaction was studied using UV-visible and fluorescence spectroscopies, dynamic light scattering (DLS), H-NMR titration and density functional theory (DFT) calculations. Theoretical analysis was carried out using DFT to justify the non-covalent type of interaction in the FHP-Fe complex and to study the electronic properties of probe FHP and FHP-Fe complex. The practical application of the FHP probe in Fe sensing was evaluated using biological samples.