"No one is above the law, but launching multiple simultaneous investigations involving a former president raises legitimate concerns about political retribution, particularly when legal and judicial institutions are still fragile," Xinhua quoted US State Department spokeswoman Marie Harf as saying in a statement.
Prosecutors in Georgia announced on Saturday that they had summoned Saakashvili for questioning on Thursday over a number of criminal cases, including a possible probe into the 2005 death of then prime minister Zurab Zhvania.
The country's current Prime Minister Irakli Garibashvili has threatened to put the former president on a wanted list in case of his failure to appear.
Saakashvili, a US ally, is not in Georgia as he left the country soon after his second term ended in November last year. Prosecutors have filed charges against several of his allies.