This paper presents an experimental investigation on the behavior of crushed clay brick (CCB) lightweight concrete (LWC) flat plate slabs under punching load. The CCB resulting from either the building process or the remnants of brick factory production lines constitutes one of the most notable wastes in the world, which motivated many researchers exploring its usage as an alternative to natural aggregates. Six LWC slabs were constructed from CCB as coarse and fine aggregates in addition to crushed brick powder (CBP). The produced concrete had a compressive strength of 25, 28, and 32 MPa and a dry density of less than 1800 kg/m3 . The tested slabs were divided into three groups (A, B, and C) according to the compressive strength. Each group had included two different tension reinforcement ratios of 0.428 and 0.616%. Based on the test results, the effect of the lightweight aggregates (LWA) was discussed and compared to codes' prediction of punching capacity. These codes include the ACI-318-19, EC-2, the Canadian code CSA-2004, ECP-203-2017, and the JSCE-2007. From the test results, it was found that the surface of punching shear failure of the tested slabs extended a distance ranged from 2.3 to 3.3 times the slab thickness measured from the column face, with the shear plane inclined at 20.3° to 27.4° to the plane of the slab. In addition, the punching shear strength can be fairly predicted by the selected international codes.