Damage in composite materials exhibits different failure behaviors across various material length scales – microscopic damage phenomena such as interface decohesion and fiber breakage subsequently leads to macroscopic failure behaviors such as structural stiffness degradation and cracking. Detailed micromechanical models are built in order to accurately capture the dependence of microscopic failure behaviors on the microstructural morphology. These micromechanical models are computationally expensive thus limited to microscale problems. On the other hand, conventional continuum damage approaches for structural analysis neglect microscopic failure behaviors and microstructural morphology. To overcome these limitations, this Parametrically Homogenized Continuum Damage Mechanics (PHCDM) model presents a multiscale modeling framework through parametric homogenization, which enables direct micro-macro connection through energy equivalence. The macroscopic constitutive law is developed based on detailed study of micromechanics, sensitivity analysis and machine learning, providing insight on damage behaviors across different material length scales with affordable computational effort. The effect of microstructural morphology on PHCDM model parameters is also explored, rendering PHCDM model broader applicability under various design scenarios. This model can be easily implemented as user-subroutines in any commercial FEM packages for analyzing damage behaviors of composite structures. Compared with traditional approaches, PHCDM model exhibits higher order computational efficiency and the capability of retrieving the detailed microscopic failure behaviors, making it a great tool for material-by-design process.