<p>The advancement of novel nanocomposite materials has drawn the focus of researchers to the issue of characterization, debonding, and failure of the interface between nanofiller and matrix material. With the upgradation of computing facilities, numerical methods have been established as necessary tools for interface problems at different length scales (nano, micro, and macro) because of their capability to model the intricate interface debonding and failure processes successfully. This review article offers a comprehensive study on the historical and current investigation movements, and projections of micromechanical, continuum mechanics, and multi-scale approaches in interface characterization and failure studies. Interaction between nanoparticles and matrix materials is usually modelled through cohesive zone models through the Lennard–Jones potential. The most used numerical approaches in interface characterization and failure are reviewed. At the nanoscale, molecular dynamics and at the macro-scale, finite element methods are utilized. In molecular dynamics simulations, the atomic descriptions are given more accurately than continuum approaches but lack computational efficiency. Thus, the development of a multiscale approach coupling the molecular dynamics and finite element model is of great importance while studying interfaces, defects, or cracks. Moreover, the methodology of the coupled finite element method and molecular dynamics approaches is also discussed. This review article focuses on serving as helpful literature for scientists in the field of novel high-performance materials.</p>