Soil salinity and Waterlogging conditions are the major threats to the sustainability of irrigated agriculture lands in Egypt. About 40% of the cultivated area is affected to some extent by waterlogging and soil salinity as solely elements or together. A sample of 26 pilot areas were selected to evaluate the individual or combined effect of waterlogging and soil salinity on cotton, wheat, sunflower and rice yields. The crop yields were measured separately for waterlogged fields and those affected with salinity and waterlogging simultaneously. The extent of yield loss as result of a rise in the water table from >1.5 m to less than 1 m was 27 and 33% for wheat and sunflower crops, respectively. Whereas, it was 7 and 6% in the case of a drop of the water table to more than 1.5 m. As for cotton, a rising water table above1.5 m to 1–1.5 m and less than 1 m gave a yield decrease of about 11 and 60% respectively. The rice crop preferred waterlogging, and in contrast to other crops, gave about 7% less yield with a lowering of the water table from less than 1 m to 1–1.5 m. The wheat and sunflower yields had decreasing trends with salinity excess 4 dS m!1 and had complete failures with salinity greater than 12 dS m!1 at water table depths less than 1, 1–1.5 and more than 1.5 m. The cotton crop demonstrated a relatively higher salinity tolerance under a water table deeper than 1 m. However, this crop could not survive at salinity levels excess 12 dS m!1 at water table depth of less than 1 m. The rice crop was a complete failure at salinity level of greater than 12 dS m!1 under water table depths less than 1 and 1–1.5 m. The combined effect of waterlogging and salinity was more harmful to crop yields when compared with the individual effect of waterlogging. The combined analysis of waterlogging and salinity on crop yields gave a good sensitivity for the salinity-yield relationships and verified the magnitudes of subsurface drainage