Myotonic dystrophy (MD) is an autosomal dominant disorder primarily characterized by myotonia. The present study describes the case of a 42-year-old woman who was transferred to the authors' department with acute abdomen and restrictive respiratory failure. Computed tomography revealed a 15-cm right ovarian tumor and atelectasis. An abdominal right salpingo-oophorectomy was performed under general anesthesia. She was then extubated after surgery; however, shortly thereafter she was re-incubated due to poor oxygenation and was then moved to the intensive care unit (ICU) for a further analysis of weaning failure. During her stay in the ICU, weaning was attempted twice, but failed both times. The patient underwent a tracheotomy 7 days after surgery. Consultation with a neurologist suggested possible MD. Following genetic testing, type I MD with ~700-1,100 cytosine-thymine-guanine repeats in the dystrophia myotonia protein kinase gene was confirmed. The patient was then transferred to a specialty hospital at 2 months after surgery. On the whole, the case described herein suggests that clinicians need to become familiar with this disease as a differential diagnosis for post-operative weaning failure.