A planning support system and process in a workstation having an operator interface, planning process feature, a data file server, and memory feature therein, characterized in storing a planner model having data indicating a plurality of planning actions in the data file server and indicating flow among the planning actions and having process times of the planning actions, and in processes executed by the planning process feature including setting an operator model on the basis of a planning request input through the operator interface, and including determining action of a first planning action to be executed according to the planner model on the basis of the operator model and for determining a second planning action to be executed following the first planning action, and including storing data needed for process of the second planning action into the memory feature until the process of the second planning action is started after process of the first planning action ends on the basis of the planner model. Parts of a model of the planning work usually made by man can be carried out by computer, and necessary data can be predicted according to process of the planning work of the planner to prepare in advance. This makes it possible that data supply time for the planner is made at a pace of his or her working process.