A novel method to process electrospun poly(l-lactic acid) (PLLA) membranes incorporating glass reinforced hydroxyapatite granules (gHA) interspacially between the polymeric fibers is reported, thus increasing the surface area for cellular interactions. gHA granules (≤150 μm) electrospun together with the polymer solution, lead to an average fiber diameter of 550 ± 150 nm for pristine PLLA and 440 ± 170 nm for the composite samples. An increase of the overall porosity was observed, from 79 ± 3% for the PLLA up to 88 ± 5% for the hybrid samples, keeping material’s wettability and mechanical properties. Bone-bonding ability showed that both samples induced HA crystal nucleation, but with a distinct pattern of mineral deposition. gHA microcomposite allows a better F-actin cytoskeleton organization during the initial adhesion and spreading, favoring cell-fibers and cell-to-cell interactions and enhanced alkaline phosphatase activity, making them potential candidates for bone healing strategies.