<p>The Al-Si cellular microstructure in additively manufactured AlSi10Mg plays a pivotal role in dictating its mechanical properties, such as strength and work-hardening. However, the micro-mechanism leading to the inter-relationship between the mechanical properties and microstructure is not yet well understood. Therefore, this investigation explores the processing-structure-property correlation in AlSi10Mg using a realistic 3D microstructure-based crystal plasticity (CP) approach. The work hardening in AlSi10Mg has been explored based on two mechanisms: (i) load bearing by the Si-phase and (ii) dislocation-driven hardening. The strain incompatibility introduced by the harder Si-phase generates geometrically necessary dislocations, which influence the hardening behavior. The role of the slip system interaction based on the slip activity on all active slip planes was also explored in understanding the work hardening behavior. The transformation in silicon morphology after the heat-treatment changes the interaction of dominant slip systems, thus leading to higher work hardening in the as-built condition during tensile deformation. The result of this study predicts that the tailoring of the Al-Si cellular structure can help to achieve the desired mechanical properties in the additively manufactured AlSi10Mg.</p> Graphic Abstract <p></p>