In the present paper, a novel double cation target colorimetric sensor was developed for the detection of Al (III), and Fe (II) ions. It was composed of ascorbic acid in a polyazomethine matrix, and polyazomethine was used to form a homogenous matrix for mixing ascorbic acid. The photophysical properties of the colorimetric sensor were clarified by using UV & ndash;Vis and fluorescence spectrophotometers. It was found that the developed sensor was exhibited good naked eye selectivity, and sensitivity toward Al (III), and Fe (II) ions with excellent photostability. Furthermore, the detection limit of the sensor was calculated as 0.398 mM (0.096 ppm) and 0.185 mM (0.051 ppm) for Al (III), and Fe (II), respectively. The applicability of the colorimetric sensor in environmental (tap and sea waters) and biological (Bovine serum albumin) solutions was also studied, and the results exhibited that the developed sensor could be successfully applied to monitoring environmental and biological samples.