The Old Persian alphabet seems relatively young. It was created artificially around the 520s BC. Old Persian was based on the Sumerian-Akkadian system. The script consisted of 36 letters, 5 hieroglyphs and a sign for separating words. Some letters could simultaneously denote both a simple consonant and a syllable.

The most famous monument of the Old Persian alphabet is the trilingual monumental inscription on the Behistun rock.