Harpocration was an author of a medical and astrological epistle believed to have lived in the 2nd or 3rd century CE. He is not attested in major historical or literary reference works. The name was common in antiquity. The most famous figure bearing it was Valerius Harpocration of Alexandria, a 2nd-century lexicographer. Another Harpocration, mentioned by the physician Galen, was a doctor of the Pneumatist sect, though no astrological writings are associated with him.

The only known work attributed to this Harpocration is an epistle on medicine and astrology. No title, surviving fragments, or further details of this specific text are recorded in standard sources.

The figure's historical significance cannot be determined from the scant available evidence. The described work reflects the syncretic intellectual environment of the Roman Imperial period, in which astrology, known as iatromathematics, was integrated into certain strands of Hellenistic medical practice.