For the degree granted by Soviet institutions, see Doctor of Sciences.

Doctor of Science (Latin: Scientiae Doctor), usually abbreviated Sc.D., D.Sc., S.D., D.S., or Dr.Sc., is an academic research degree awarded in a number of countries throughout the world. In some countries, "Doctor of Science" is the title used for the standard doctorate in the sciences; elsewhere the Sc.D. is a "higher doctorate" awarded in recognition of a substantial and sustained contribution to scientific knowledge beyond that required for a Ph.D. It may also be awarded as an honorary degree.