Abstract This paper introduces the regular decoupling field to study the existence and uniqueness of solutions of two-point boundary value problems for a class of ordinary differential equations which can be derived from the maximum principle in optimal control theory.The monotonicity conditions used to guarantee the existence and uniqueness of such equations are initially a special case of the regular decoupling field method.More Locomotive generally, in case of the click here homogeneous equations, this paper generalizes the application scope of the monotonicity conditions method by using the linear transformation method.In addition, the linear transformation method can be used to handle the situation where the monotonicity conditions and regular decoupling field method cannot be directly applied.These two methods overall develop the well-posedness theory of two-point boundary value problems which has potential applications in optimal control and partial differential equation theory.