Additive manufacturing (AM) is a novel technology whichallows fabrication of complex geometries from digitalrepresentations without tooling. In addition, this technologyresults in low material waste, short lead times and cost reductionespecially for the production of parts in low quantities. Currentadditive manufacturing processes developed for thermoplasticsandwich panels suffer from an unavoidable weak mechanicalperformance and low thermal resistance. To overcome theselimitations, emphasis is paid in this study on direct write AMtechnology for the fabrication of short carbon fiber-reinforcedsandwich panel composites. Sandwich panels using differentinfill densities with high strength (>107 MPa), and high shortcarbon fiber volume (46%) were attained successfully. Inparallel to the strength enhancement, these sandwich panelspossessed reduced densities (0.72 g/cc3) due to their lightweightlattice core structures. The mechanical performance of thecreated sandwich panels was examined and compared to theunreinforced, base ink structures by performing compressiontests. Successful fabrication and characterization of theadditively manufactured thermoset-based carbon fiberreinforced, sandwich panels in this study can extend the range ofapplications for AM composites that require lightweightstructures, high mechanical performance as well as the desiredcomponent complexity.