Pleurotus ostreatus is the second cultivated and most popular edible mushroom after Agaricus bisporus worldwide. As dietary supplements, nutraceuticals like Pleurotus ostreatus that go beyond the usual health benefits of mushrooms are becoming more popular. The objective of this study is to put together a summary of the nutrition information and link it to the possible health benefits and health-improving effects of eating oyster mushrooms. This review is based on secondary data from 102 published articles about P. ostreatus. All papers were examined following predetermined criteria for inclusion and exclusion, and this study contained 83 publications. The high nutritional content and beneficial health effects make P. ostreatus a high-quality food. It makes up for the lack of protein by switching between a diet based on wheat, rice, and maize. Nowadays, P. ostreatus is famous precious functional food ingredients due to the fact they may be cholesterol-free and low in calories, carbohydrates, fat, and sodium. Side by side, they offer crucial nutrients including riboflavin, selenium, potassium, niacin, proteins, and fiber.