Mar Ishodad of Merv (Classical Syriac: ܡܵܪܼܝ ܝܼܫܘܿܥܕܵܕ ܡܲܪܘܼܙܵܝܵܐ, romanized: Māri Ishoʿdāḏ Maruzāyā; fl. AD 850) was a bishop of Hdatta during the Abbasid Caliphate (near current-day Mosul, Iraq) and prominent theologian of the Church of the East, best known for his Commentaries on the Syriac Bible.