Iku-Shamagan (, i-ku-<sup>D</sup>sha-ma-gan, ) was a King of the second Mariote kingdom. He is one of three Mari kings known from archaeology, Ikun-Shamash probably being the oldest one. Another king was Ishqi-Mari, also known from an inscribed statue.
In their inscriptions, these Mari kings used the Akkadian language, whereas their contemporaries to the south used the Sumerian language.
A vase mentioning Iku-Shamagan "in an early semitic dialect" is also known:
Iku-Shamagan is known from a statue with inscription, discovered by André Parrot in 1952. The statue, in the National Museum of Damascus, was restored by the Louvre Museum in 2011.
Iku-Shamagan's votive statue was dedicated through an inscription on the back of the statue:
The statue was discovered in Mari, in the Temple Ninni-zaza.
The statue was heavily damaged during the conquest by the armies of the Akkad around 2300 BC.