Crates of Mallus (Greek: Κράτης ὁ Μαλλώτης, Krátēs ho Mallṓtēs; fl. 2nd century BC) was a Greek language grammarian and Stoic philosopher, leader of the literary school and head of the library of Pergamum. He was described as the Crates from Mallus to distinguish him from other philosophers by the same name. His chief work was a critical and exegetical commentary on Homer. He is also famous for constructing the earliest known globe of the Earth.
He was born in Mallus in Cilicia, and was brought up at Tarsus, and then moved to Pergamon, and there lived under the patronage of Eumenes II, and Attalus II. He was the founder of the Pergamon school of grammar, and seems to have been at one time the head of the library of Pergamon. Among his followers were Hermias (Κρατήτειος Ἑρμείας mentioned in sch. Hom. Il. 16.207a), Zenodotus of Mallus and Herodicus of Babylon.
He visited Rome as ambassador of either Eumenes, in 168 BC, or Attalus in 159 BC. Having broken his leg after falling into an open sewer, he was compelled to stay in Rome for some time and delivered lectures which gave the first impulse to the study of grammar and criticism among the Romans.
Crates made a strong distinction between criticism and grammar, the latter of which he regarded as subordinate to the former. A critic, according to Crates, should investigate everything which could throw light upon literature; the grammarian was only to apply the rules of language to clear up the meaning of particular passages, and to settle the text, prosody, accentuation, etc. From this part of his system, Crates derived the surname of Kritikos.