n construction project operation, often there is a project cost variance in terms of thematerial, equipments, manpower, subcontractor, overhead cost, and general condition. Material is themain component in construction projects. Therefore, if the material management is not properlymanaged it will create a project cost variance. Project cost can be controlled by taking correctiveactions towards the cost variance. The objective of this research paper is to identify the main cause of the cost variance and to recommend the corrective actions. The approach to serve that objective is byconducting surveys to high rise building construction projects in order to identify the cause of projectcost variance in material purchasing, and by interviewing experts in order to obtain recommendationsin taking corrective actions. Method Analysis used in this research is Delphi method. The result of theresearch shows that the corrective action towards the variance of the material purchasing cost isactually a preventive action (before process)