Katherine Augusta Westcott Tingley (1847, Newbury, Massachusetts - 1929) was a social worker and prominent Theosophist.

Tingley was a social worker in New York when she met William Quan Judge. She joined the Theosophical Society on October 13, 1894. In 1895, disputes between Judge and Annie Besant lead to a split, with Judge taking most of the American section with him, and leading it for one year until his death in 1896. At that point Tingley became the new head of the organization. On February 13, 1900, she transferred the Society's international headquarters from New York City to Lomaland at Point Loma, California.

Tingley founded the Raja-Yoga School and Theosophical University in Point Loma.