A construction project consists of a variety of contracts for the completion of work. The large number of contracts involved in a single project increases the likelihood that disputes will arise between the parties involved regarding the terms of service. Actually, there are many disputes that are caused by a change 0 order. While such disputes should be settled by interpreting the terms stipulated in the agreement entered between the two parties, the process of dispute settlement is often restricted to arbitration and lawsuit, and as a result the parties tend to avoid it due to its inefficiency. For this reason, in Korea it is hard to find cases of interpreting terms of service, while in the U.S. it is easy to find diverse cases of interpreting terms of service, since there is a process of dispute settlement by each stage by the party who has placed an order. Therefore, this study presents analysis of case studies of contract changes, looking specifically at changes in the scope of the work, changes in quantity, changes in the period of implementation, changes in the method of implementation or attitude, changes in items provided by the government or the delivery place, and the acceptance of such change procedure by a contractor, and the adjustment of a reduction.