The unnamed boy had posted on the Facebook expletive and was critical of Singapore.
In his Facebook post, he had said that the day he leaves Singapore, he is going to take a "big big revenge", "spit everywhere" and "plant bombs on Marina Bay Sands, one of the two casino-based resorts in Singapore.
An Internet user who saw the posting made a police report last Saturday, The Straits Times said.
The four line posting has since been removed. The boy studies at an Indian school here. The school has suspended the boy.
Under Singapore law, those found guilty of falsely threatening terrorists acts face a fine of 100,000 dollars or jail term of five years or both.