In enzymology, a psychosine sulfotransferase (EC 2.8.2.13) is an enzyme that catalyzes the chemical reaction:

3'-phosphoadenylyl sulfate + galactosylsphingosine ${\displaystyle \rightleftharpoons }$ adenosine 3',5'-bisphosphate + psychosine sulfate

Thus, the two substrates of this enzyme are 3'-phosphoadenylyl sulfate and galactosylsphingosine, whereas its two products are adenosine 3',5'-bisphosphate and psychosine sulfate.

This enzyme belongs to the family of transferases, specifically the sulfotransferases, which transfer sulfur-containing groups. The systematic name of this enzyme class is 3'-phosphoadenylyl-sulfate:galactosylsphingosine sulfotransferase. Other names in common use include PAPS:psychosine sulphotransferase, and 3'-phosphoadenosine 5'-phosphosulfate-psychosine sulphotransferase.

• Nussbaum JL, Mandel P (1972). "Enzymic synthesis of psychosine sulphate". J. Neurochem. 19 (7): 1789–802. doi:10.1111/j.1471-4159.1972.tb06224.x. PMID 5042474.