Small red dots in the groin may be caused by syphilis, or may be a symptom of other diseases such as ringworm, allergies, etc., and you need to go to the hospital in time to find out the cause of the disease. 1. Syphilis: Syphilis is a chronic sexually transmitted disease caused by the syphilis spirochete, and different stages of the disease have different clinical symptoms. The disease has different clinical symptoms at different stages. The first stage is characterized by a hard chancre, and the second stage is characterized by a syphilis rash on the skin and mucous membranes of various parts of the body, which can be manifested as a red spot in the groin. 2. Ringworm: Ringworm is a common fungal infectious skin disease, and the common germ is red trichophyton. When the patient’s body is infected, red spots, pimples and scales can appear in the groin. 3. Allergy: small red spots in the groin may be caused by allergy. If the patient comes into contact with some allergens such as pollen, dust mites on the local skin stimulation will often cause local inflammatory reaction of the skin, thus appearing red spots. There are many reasons for the appearance of small red dots in the groin, when the patient appears to be uncomfortable, should immediately go to the hospital for medical treatment.