The paper defines organization communication validity of the construction project as the integrative reflection of communication efficiency and communication effect based on the concept of validity from Peter F. Drucker. According to the concept of organization communication validity, the paper establishes the evaluating indicator system of organization communication validity of the construction project, carries out the synthetic evaluation for organization communication validity of the construction project using fuzzy and analytical hierarchy process (AHP) method, designs questionnaire of organization communication validity of the construction project based on Downs communication system, selects four enterprises of real estate, construction design, general contractor and supervisor as research objects to perform empirical research and proves the practicability of the evaluating model.