In the bridge design specifications of Vietnam (22-TCN-272-05), the redanduncy is an important input data, which can strongly effect the dimension of structure and scope of design from increasing or reducing the value of structure behavior in the checking equation. However, there is no research on how to determine this coefficient nor a simple methodology to select the right redundancy coefficient in designing bridge in Vietnam. Therefor, it is necessary to create and improve a guideline to calculate the redundancy, which has to be simple and useful enough, to be appled by the engineer. That is the reason why we choos the topic “Redundancy of bridges in Vietnam”.