The Yavanajātaka (Sanskrit: yavana 'Greek' + jātaka 'nativity' = 'nativity according to the Greeks') of Sphujidhvaja is an ancient text in Indian astrology.
According to Pingree, it is a later versification of an earlier translation into Sanskrit of a Greek text, thought to have been written around 120 BCE in Alexandria, on horoscopy. Based on Pingree's interpretation, the original translation, made in 149–150 CE by "Yavanesvara" ("Lord of the Greeks") under the rule of the Western Kshatrapa king Rudrakarman I, is lost; only a substantial portion of the versification 120 years later by Sphujidhvaja under Rudrasena II has survived. However, according to the recent research by Mak based on a newly discovered manuscript and other documents, Pingree's date interpretation as well as a number of crucial readings such as zero and other bhūtasaṃkhyā were based on his own emendation, not supported by what was written on the manuscripts. Furthermore, traditionally Yavanesvara and Sphujidhvaja were understood as referring to the same person, the former being an epithet to the latter, according to authors such as Bhaskara and Utpala. The date of the Yavanajātaka according to Mak is now revised to between 4th and 6th century CE.
Yavanajataka is one the earliest known Sanskrit works referencing western horoscopy. It was followed by other works of Western origin which greatly influenced Indian astrology: the Paulisa Siddhanta ("Doctrine of Paul"), and the Romaka Siddhanta ("Doctrine of the Romans"). However, the earliest known Sanskrit work on horoscopy is Vedanga Jyotisha
It was translated by David Pingree into English, which was published as volume 48 of the Harvard Oriental Series in 1978.