Two-dimensional indium nitride (InN) exhibits promising application prospects in flexible electronics owing to its attractive intrinsic properties. In practical applications, materials are inevitably subjected to various types of strain induced by substrates, defects, and other factors, which significantly modifies their properties. Therefore, elucidating the structural and electronic evolution of InN under diverse strain conditions is critical for promoting its practical applications. Using first-principles calculations, we systematically investigate the mechanical and electronic responses of monolayer InN under complex strain conditions, including various strain modes and combined strain configurations along different crystallographic directions. Our results demonstrate that the in-plane properties of InN show pronounced anisotropy, originating from the orientation-dependent bonding characteristics along different in-plane crystallographic directions. Strain can effectively modulate the bandgap of the structure while deforming its crystal geometry. With increasing strain, the bandgap gradually decreases, and sufficiently large strain along specific directions induces a semiconductor-to-metal transition. By combining different strain loading schemes, we identify mechanical and electronic responses distinct from those under pure strain, implying the complexity and tunability of strain-governed behaviors. This work reveals the structural evolution mechanisms of monolayer InN under complex strain conditions, providing significant theoretical guidance for the design and development of InN-based strain-engineered semiconductor devices.