Government transparency should be embedded in the designs of e-Government systems. Lack of transparency can prevent the public from participating actively in government operation, such as by raising questions and protesting ill-advised decisions, which in turn may lead to concealment official graft or favouritism. However, it is also difficult to guarantee that designs of e-Government systems are consistent with real requirements in terms of having desired properties, such as transparency. In this paper, we introduce formal methods into the field of e-Government (or public administration) for formalizing designs of e-Government systems and analyzing if the designs satisfy desired properties, in particular transparency. To the best of our knowledge, we are the first to try to formally define and analyze the notion of transparency based on the formalized designs of e-Government systems. The formal method that we used is an equation-based method - the OTS/CafeOBJ method. In using this method, an e-Government system design is first modeled as an Observational Transition System (OTS), a kind of transition system that can be straightforwardly written in terms of equations. The OTS is then specified in CafeOBJ, an algebraic specification language. And lastly, we express the transparency properties as invariants of the OTS, and verify the invariants by using the CafeOBJ system as an interactive theorem prover.