A smartphone is one of the best candidate devices on which context based services can be provided because a smartphone has considerably powerful computing ability and large memory capacity and it is a personal belonging. One of the most important factors of context is the moving status of the smartphone. For example, if the smartphone is not moving and the user is in an exhibition room then we can conclude that the user is watching an exhibit. This paper proposes an algorithm of determining the moving status of a smartphone for the first time. Our test results showed that the proposed algorithm is 100% correct.