Abstract: Action calculi have been introduced as an abstract mathematical structure, and it has been shown thatλ calculus, process algebra,γ calculus and functional language can be represented in the framework of action calculi. As an application of action calculi, a higher-order action calculus for a typical sequential imperative language SIL is defined, where higher-order action is used for defining loop. The correspondence between operational semantics and action calculus semantics of SIL is established. Finally, the method to define controls and control rules for sequential computations are discussed. The effort of this paper not only shows that sequential computation can also be represented in action calculus expediently but also prove the expressive power of action calculi.