Research journals and conferences publish papers after reviewing the submitted manuscripts on the scholarly peer review system. Process modeling techniques, including UML activity diagrams or Business Process Modeling and Notation, have been used to model the peer review process. However, some journal editors and developers experience difficulty identifying the next steps or commands based on manuscript states and understanding the next manuscript state with the command. For example, if the manuscript state is in the ‘review complete’ state, the following activities could include several commands, including decisions on manuscript publication or clarification on the review, which transits to different states. Research on modeling manuscript states has rarely been found in the literature. This paper uses a state machine diagram to model the manuscript states and events causing state transition, helping journal editors and developers understand manuscript states. Several journal editors responded positively to the proposed models. Applying state modeling techniques would help better identify and control appropriate commands during the development of the peer review system.