Botulinum toxin is a neurotoxin produced by Clostridium botulinum, and has a role in muscle relaxation. Type-A botulinum toxin (TABX) is used widely in cosmetics and rehabilitation fields. TABX can be used to remove wrinkles, treat facial spasms, reduce muscular tension, and relieve pain. However, adverse reactions such as respiratory paralysis, swallowing difficulties, upper-eyelid ptosis, and local necrotizing fasciitis are associated with its use. Herein, we describe a case of diffuse alveolar hemorrhage caused by intramuscular injection of TABX in both lower limbs. Cases of diffuse alveolar hemorrhage after injection of TABX into the muscles of both lower limbs are rare. For patients with an allergic constitution, a skin test should be undertaken when TABX to prolong the observation time. If the reaction is confirmed to be related to TABX, antitoxin treatment should be implemented immediately.