A comprehensive review by authors on well-known lattice cell topologies composed of metals and polymers having sizes ranging from micro to nano-length scale revealed the simple-cubic (SC) plate lattice exhibits the highest elastic modulus and yield strength. In this study, a novel simple-cubic-octahedral (SCO) plate lattice is proposed by reinforcing octahedral plates with SC-plate lattice. Finite element simulations demonstrated that the SCO-plate lattice exhibited the highest elastic modulus and yield strength among the strut, surface and plate lattices investigated previously. Furthermore, the SCO-plate lattice displayed a high degree of isotropy. Also, the proposed lattice absorbed significantly higher energy compared to the SC-plate lattice for a relative density of 40%. A new semi-analytical framework is also presented to evaluate the elastic modulus of the SCO-plate lattice. The homogenization scheme in Abaqus was used to evaluate the effective properties, resulting in a significant reduction in computational time. The effects of geometrical parameters on the mechanical properties of the SCO-plate lattice were also studied using a design of experiment approach. The quasi-static compression tests were performed on 3D-printed lattices fabricated using a multi-jet fusion technique to validate the numerical simulations. The proposed plate lattice can be an excellent choice for lightweight applications.