The growing concern for the environment makes projects that aim and highlight the Sustainable Development Goals (SDGs) viable, including reducing food waste (and its reuse) and using environmentally friendly technologies. Lychee (Litchi chinensis), commonly consumed fresh, can generate many byproducts, such as the peel, which has significant concentrations of bioactive compounds. To obtain these compounds, ultrasound can be used to promote obtaining high-quality extracts with reduced environmental impact. Thus, this study aims to verify the influence of ultrasound-assisted extraction of lychee peel using an aqueous solvent in obtaining bioactive compounds and their characterization regarding their antioxidant activity and profile of phenolic compounds. Extractions were carried out according to experimental design 2³ with triplicates at the central point, using the independent variables: Power (20%, 40%, 60%), Time (5, 10 and 15 min) and Concentration (0.1; 0.067 and 0.05 g mL^-1). The extracts were characterized for their antioxidant activity (DPPH and ABTS), total phenolic compounds, and phenolic compound profile. From the results obtained, it was verified that potency, time, and concentration significantly influenced both the phenolic content and the antioxidant activity of the extracts. Extraction time proved to be the most significant variable, followed by concentration. The results also revealed the presence of several phenolic compounds in lychee peel extracts, emphasizing Procyanidin B2, Epicatechin, Quercetin 3-Glucoside, and Kampeferol 3-Glucoside. Through the proposed planning, it was found that the best extraction condition was observed at the longest extraction time and the lowest power and concentration values. Therefore, extracting lychee peel using ultrasound can be a promising strategy for obtaining extracts rich in bioactive phenolic compounds with high antioxidant activity.