The application of input-output production function to make production plan outline and product scheduling of make-to-order enterprises are studied. The manufacturing system is divided into production nodes or process centers. According to the rule of dividing the manufacturing system, the route of each varied productions can be described by the production nodes they pass. The input-output relations among production nodes and the dynamic and stochastic factors existing generally during production processes can be reflected by the model of dynamic & stochastic production function, in order that planners can estimate the stochactic factors which influence the manufacturing time. On the basis mentioned above of , considering the specificity of make-to-order enterprises, the production plan outline is made by the model of static production function, and the product scheduling is made by the model of dynamic & stochastic production function.