Martha Elizabeth Reifsnyder (17 January 1858 - 3 February 1922) was an American physician, surgeon, teacher, and missionary. Early in her career, she was the only woman physician native to Perry County, Pennsylvania. She served as medical missionary in China, and opened the first woman's hospital in Shanghai, the Margaret Williamson Hospital. The Elizabeth Reifsnyder Hospital was a maternity building, the first one in China. Reifsnyder is remembered for performing "the first ovarian cyst operation by an American woman physician on a Chinese woman". She became internationally known after removing a 33-pound ovarian cyst from one of her Chinese patients.