The strength and structure of broadband heating rate directly drives the global atmospheric circulations and is largely determined by cloud threedimensional (3D) structures. Heating rate profiles and fluxes of three cloud fields resolved by Cloud Resolving Models (CRM) are simulated by a broadband 3D Monte Carlo radiative transfer model, which gives a quantitative and statistical estimate about the effects of cloud 3D structures on radiation in high resolution by comparing with Independent Pixel/Column Approximation (IPA/ICA). Two parameters are defined to describe the vertical distribution and strength simultaneously. The results show that the impacts of cloud 3D structures on radiation are very significant under high resolution conditions and different kinds of cloud fields have various characteristics. A direction of the revising on current heating rate calculation scheme in existing atmospheric models due to cloud 3D structures is raised.