Blisters on the lips of pregnant women are mostly a viral skin disease caused by herpes simplex virus type I. Mainly, red papules with rice-like blisters in clusters can be seen on the lips and around the mouth of pregnant women, and they are mostly painful, usually without any effect on the pregnant woman or the fetus. If the patient develops a significant tingling sensation, a mixture of topical erythromycin eye ointment and penciclovir cream can be used. If the patient has increasing blisters, oral vitamin B12 can be taken, and a mixture of mometasone furoate cream and acyclovir cream can be used topically. During the treatment period, patients need to abstain from spicy and stimulating foods, while maintaining a regular routine, paying attention to rest, reducing late nights, and avoiding overly hot food.