Bioactive compounds like piperine (alkaloids) offer a variety of health benefits due to their biological and pharmacological potential. Piperine has been revealed to have anti-inflammatory, anti-aging, anti-diabetes, anti-bacterial, anti-ulcer, and anti-carcinogenic characteristics. Recent research has been conducted to extract piperine using effective and environmentally friendly techniques. In this study, we sought to assess the potential and efficacy of natural deep eutectic solvents to extract piperine from black pepper seeds using an ultrasound-assisted extraction technique. A Box–Behnken design combined with response surface methodology was used to evaluate the optimum extraction conditions of piperine. Extraction efficiency was evaluated based on the extraction yields of piperine, antioxidant activity, total polyphenols, and total flavonoids. The results showed that the choline chloride-citric acid-1,2-propylene glycol combination (1:2:2 molar ratio) with 25% (v/v) of water was the most effective at extracting piperine from black pepper. It was found that the extraction yield of piperine was significantly influenced by the liquid–solid ratio and extraction time. The optimal extraction conditions were determined and it was found that antioxidant activities and total polyphenol content in the piperine-rich extracts were remarkably related to the piperine content. The piperine extract purity was found to be 90%. Our results indicate that black pepper could be used as a functional food application.