Recurrent oral ulcers that is, recurrent aphthous ulcers, leukemia oral ulcer symptoms and recurrent aphthous ulcers are similar, the two can be identified through the systemic symptoms of leukemia, such as genital ulcers, skin lesions, ophthalmitis, etc., details are as follows. 1. Genital ulcers: about 75% of leukemia patients may have genital ulcers, which are deep and large, accompanied by severe pain and slow healing, and may occur in the vulva, vagina, perianal area, cervix and other parts of the body. 2. Skin damage: about 80% of leukemia patients have skin damage, which can have various manifestations, such as erythema nodosum, herpes, papules, acne-like rash, erythema multiforme, erythema annulare, and so on. 3. Ophthalmitis: about 50% of leukemia patients may develop ophthalmitis, which manifests as blurred vision, decreased visual acuity, eye congestion, photophobia and tearing, and foreign body sensation. Leukemia may also have other systemic symptoms, it is recommended to go to the hospital in a timely manner, after a clear diagnosis for targeted treatment.