Guava is a vital fruit worldwide, especially in Pakistan, and due to its nutritional value famous in each age group. Due to a very short shelf life, the marketing and export of this fruit faced severe constraints. Therefore, in the current study, edible coating of chitosan (0, 0.5, 1.0, 1.5, and 2.0%) was evaluated on postharvest shelf life when guava fruits were stored (room temperature and 4 °C temperatures) for 12 days. The chitosan treated coating fruits have shown reduced total sugars and malondialdehyde levels compared to untreated control samples. However, a significant difference (p ≤ 0.05) in total sugar and malondialdehyde levels exists between samples stored in m compared to refrigerated temperature (4 °C). The chitosan-coated samples have shown a greater amount of vitamin C, quercetin, rutin, and total phenolic contents than control samples. However, these nutritional parameters' levels were significantly different (p ≤ 0.05) in samples stored at room than samples stored at refrigerated temperature. However, the levels of crude fiber, potassium, and sodium were found statistically nonsignificant (p ≥0.05) in control versus chitosan treated coating treatments. The findings have documented that the coatings of 1.5 and 2.0% were most effective for extension in shelf life and maintaining the nutritional attributes of guava fruit.