Lime (Citrus aurantifolia v.) susceptibility to chilling injury and its limited shelf life are common challenges in postharvest management. There has been a growing trend of replacing harmful chemicals with natural substances that pose no harm to plants, the environment, or humans. To address this issue, we conducted a factorial experiment using a randomized complete block design with four replications. Our study aimed to evaluate the impact of different concentrations of salicylic acid (SA) (0, 1, 2, and 3 mM) on the enzymatic activity of limes during storage (0 and 60 d). Experimental conditions maintained a temperature of 4 ± 1 °C and a humidity of 85 ± 2%. Several enzymes were measured, including phenylalanine ammonia-lyase (PAL), peroxidase (POD), superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), antioxidant activity, and chilling injury (CI). Our results indicated that all concentrations of SA led to increased activity of antioxidant and defensive enzymes in the fruits. At 3 mM SA, the activity of antioxidant enzymes increased by 4.06%, and SOD activity increased by 13.2%. The treatment of 2 mM SA increased POD (24.53%) and CAT (86.3%) activities. Also, 1 mM SA enhanced APX enzyme activity by 27.78%, while PAL enzyme activity decreased by 38.35%. In sum, all SA concentrations, particularly 2 and 3 mM, reduced the CI index. Our study demonstrated that increasing the SA concentration significantly extended the shelf life of Mexican lime fruits. This finding is supported by the observed increase in antioxidant enzyme activities.