<p>To address the declining availability of rubberwood in Southeast Asia, we explored the use of oil palm residues—oil palm trunk (OPT), frond (OPF), and empty fruit bunch (EFB)—as alternative raw materials for the production of medium-density fiberboard (MDF). In particular, we focused on the effects of compression on the fiber characteristics and the bending properties of MDF. Compression processing was applied under various conditions, including differences in biomass type, moisture content before compression, compression method, and pressing pressure during board formation. The influence of these factors on fiber morphology was examined, and the relationship between refined fiber length and the mechanical performance (in terms of the modulus of rupture and the modulus of elasticity) of MDF produced from those fibers was evaluated. Compression conditions influenced fiber size distribution by reducing chip dimensions and limiting maximum fiber length according to die hole diameter and compression method. These changes, in turn, affected the bending properties of MDF, with longer fibers generally enhancing the modulus of rupture (MOR) and the modulus of elasticity (MOE), although the effects varied by biomass type. The implications are that oil palm biomass is a potential alternative raw material for the production of MDF and that optimizing the compression parameters can improve the performance of the resulting MDF.</p>