Lead is an environmental pollutant that has been present for a long time and has harmful effects on human health. The essential task of protecting public health requires sensitivity and selectivity in monitoring and removing Pb2+ from the environment. NH2‐Al‐MOF was utilized to create a chemical sensor that can quickly detect Pb2+ ions. By combining the Al–metal–organic framework (MOF) with 2‐Acetyl‐4‐methylpyridine, the 2A4MP=N‐Al‐MOF sensor was developed. The NH2‐Al‐MOF and 2A4MP=N‐Al‐MOF sensor were characterized by X‐ray photoelectron spectroscopy (XPS), Brunner–Emmet–Teller (BET), X‐ray diffractometer (XRD), Fourier transform infrared (FT‐IR), and scanning electron microscopy (SEM). Characterization results indicate that 2‐Acetyl‐4‐methylpyridine was effectively incorporated into the Al‐based MOF, and the 2A4MP=N‐Al‐MOF sensor's pore structure is primarily made up of mesopores. To determine the optimal conditions for detecting Pb2+ ions using the 2A4MP=N‐Al‐MOF sensor via fluorescence measurement, several experimental studies have been carried out. A steady spectroscopic signal can be achieved with a sensor that has a response time of below 30 seconds. According to ICH guidelines, the suggested methods underwent validation for LOD, LOQ, linearity, and precision. The results show that the 2A4MP=N‐Al‐MOF chemosensor has a high sensitivity and selectivity toward the Pb2+ analyte, with a detection limit of 0.171 ppm and a linear range of 0.0–2.0 ppm. The 2A4MP=N‐Al‐MOF chemosensor also exhibited good reproducibility, with a relative standard deviation of less than 3%. As a result, the Pb2+ ions were sensitively and selectively identified in various environmental water samples using the 2A4MP=N‐Al‐MOF sensor.