This study provides a detailed report on the physicochemical, bioactive components, and volatile profiles of diverse sour cherry (Prunus cerasus) cultivars to identify the cultivar(s) containing high health-promoting components. Physiological characteristics (fruit weight, size dimensions, moisture, color attributes, total soluble solids, pH, titratable acidity, maturity index, nutritional bioactive components (total phenolic, total anthocyanin content, and total flavonoids), antioxidant activity, and volatile profile of 10 sour-cherry cultivars, consisting of dark red Morello type and clear fruit flesh Amarelle type, were studied. The total phenolic content was in the range of 123.24–289.91 mg gallic acid equivalent/100 g FW (fresh weight), total flavonoids (1340.23–2831.91 mg quercetin equivalent/100 g FW), and total anthocyanins (225.43–485.66 mg cyanidin-3-glucoside equivalent (CGE)/100 g FW) in different sour-cherry cultivars, showing significant diversity in such health-promoting compounds. In vitro antioxidant activity assessed by ferric reducing antioxidant potential was observed in the range of 658.18–1483.37 mg Trolox equivalent (TE)/100 g FW and by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) at 384.36 and 931.85 mg TE/100 g FW. A total of 10 phenolic components, including five hydroxycinnamic acids, three flavonoids (flavanols), and one anthocyanin, have been identified and quantified by high-performance liquid chromatography. Hydroxycinnamic acids represented 40%–60% of total phenolic components, while flavonoids and anthocyanins amounted to 20% each in total phenolic composition. The volatile profile of sour-cherry cultivars revealed that aldehydes, alcohols, ketones, esters, monoterpenes, acids, sugars, and hydrocarbons were the predominant volatiles present in sour cherry.