This study was carried out to determine the effects of screw and back panel on the corner joints in case furniture produced from medium density fiber board MDF, and particle board (PB). For this purpose, the different test panels, the edges of which were covered or uncovered with solid wood or massive and back rebated, not back rebated samples, were used and the types of "L corner joints" were manufactured. Also, the plywood used for back panel had a thickness of 4 mm. Compression and tension strength tests were applied on the corner joints in accordance with ASTM-D 143-83 standards. As a result, the highest tension strength was obtained in covered edges of MDF as 181.7 Nm, the lowest in rebated and uncovered samples as 78.7 Nm, the highest compression strength was obtained in rebated and covered samples as 178.7 Nm, and the lowest was observed in unrebated and uncovered samples as 79.5 Nm. In conclusion, the edges of cupboard panels should be rebated and covered with solid wood or massive wood in Case furniture. (c) 2007 Elsevier Ltd. All rights reserved.