Natural fillers have been used as reinforcing material for many years in the research field of biobased polymers. It is widely known for being low cost, eco-friendly, and easily available. The biobased polymer composites have strong future prospects in the application for transportation and packaging industries. In this study, the biobased composite is fabricated at 40 % hazelnut shell flour (HSF) content with 2.5, 7.5, and 10 % of inorganics-based additives like mica, glass ball, talc by extrusion, and press molding method. The mechanical and thermal properties and water absorption of those composites are investigated. The result reveals that inorganic powder-filled composites shows clearly higher impact energy than pure polylactic acid (PLA). However, there was a general decrease in tensile and flexural properties with the addition of mica and glass ball powders, and an increase in properties between 10 % and 30 % was determined with the addition of talc powder (7.5 % and 10 %). The highest flexural strength of the 7.5 % talc-filled PLA/HSF composites is obtained as 51 MPa and the highest tensile strength of 22 MPa was observed for both 7.5 % and 10 % talc. The scanning electron microscopic image reveals the uniformly distributed organic and inorganic fillers and microstructural deformation of the fractured composite surfaces.