Stingrays are the most common venomous cartilaginous species found in aquatic environments. The sting on their tail can cause mechanical injuries through perforation or laceration, along with venom injection. Experimental studies on mammals have indicated potential cardiac and neurological complications because of these stings. We report the case of a 25-year-old man who was stung on the ankle by a stingray in a coastal town in Tunisia. Initially, he exhibited cardiac symptoms, specifically a first-degree atrioventricular block, as well as local inflammatory signs including pain, redness, and swelling. A transthoracic echocardiogram showed normal cardiac function. After receiving treatment that involved immersing the affected limb in warm water and administering analgesics, the local symptoms subsided, and the patient returned to a normal sinus rhythm. This case underscores the potential cardiac effects of stingray envenomation, which may be the first documented instance in humans.