S. Krishnamurthi Sastri (1900–1990) was a distinguished 20th-century Sanskrit scholar, editor, and manuscriptologist. He served as the Principal of the Madras Sanskrit College and was instrumental in the critical editing and publication of numerous rare Sanskrit manuscripts, particularly for the Adyar Library and the Sarasvati Mahal Library in Thanjavur. His extensive scholarly contributions include the multi-volume edition of the शिवरहस्यम् (Sivarahasyam) and various Tantric works such as the சரபகல்பம் (Sarabha Kalpam) and சூலினீ கல்பம் (Sri Sulini Kalpam).