Gantz American counterpart Chairman of the Joint Chiefs of Staff Gen. Martin E. Dempsey presented the award on behalf of President Barack Obama, an Israeli army statement said.
Dempsey praised Gantz, saying under his command the Israeli army will be able to stand strong in the face of a wide range of threats.
Gantz responded, saying he accepts the award on behalf of all Israel's soldiers and said it also represents the strong relationship between the two armies. He also thanked Dempsey for "tight-knit" cooperation, the statement said.
A note that accompanied the award, signed by Dempsey and U.S. Secretary of Defense Leon Panetta, stated the honor was in recognition of Gantz's outstanding and noteworthy command, the statement said.
The Legion of Merit can be awarded to U.S. military personnel as well as international and government officials.