Background: Hand, foot, and mouth disease (HFMD) is a common systemic infection that is caused by an enterovirus, normally Coxsackie A16. Generally, it affects children or immunocompromised adults. Only a few reports have described pseudomembranous conjunctivitis associated with HFMD. We aim to describe the clinical outcomes and ocular findings of a 37-year-old female with HFMD and concurrent severe pseudomembranous conjunctivitis, who was 28 weeks pregnant., Case Presentation: A female patient who was 28-weeks pregnant was referred for an ophthalmological review due to pain and injection in both eyes. The patient was hospitalized under obstetrics and gynecology and evaluated for Behcet's disease with oral and perineal ulcers. In an ophthalmic examination, both eyes were observed to have a conjunctival injection. Behcet's disease-associated conjunctivitis was diagnosed. Topical steroids and antibiotics were administered every 6 h. Two days after her presentation, a maculopapular eruption occurred on her palms. Enterovirus type 71 was detected in a serum virus antibody test, and the patient was diagnosed with HFMD. After 7 days, severe pseudomembranous conjunctivitis and corneal epithelial defects occurred in both eyes. Topical steroids were administered every 3 h, and the pseudomembrane was removed every 2 to 3 days. The pseudomembrane did not occur after 3 weeks, but corneal erosion persisted. After 3 months, the corneal erosion had completely resolved., Conclusions: HFMD-associated conjunctivitis is a rare complication in adults, however it can appear as a severe pseudomembranous conjunctivitis. In this case, the removal of the pseudomembrane and topical steroids helped improve the symptoms.