Two experiments were conducted on a clay soil of Res. & Experiment Centre, Fac. Agric., Moshtohor (Kalubia) during 2004/2005 and 2005/2006 growing seasons to evaluate the response of the following experimental factors on maize crop - Two preceding winter crops (wheat and clover). - Three tillage treatments (no-tillage, double chisel plowing and moldboard plowing + single chisel plowing). - Six nitrogen fertilization treatments (zero, 60 kg organic N, 60 kg mineral N, 120 kg mineral N, 60 kg organic N + 60 kg mineral N and 60 kg organic N + 120 kg mineral N / fed.). Results showed: - All maize characters and grain yield were markedly enhanced when preceded by clover. Growth of weeds in maize was greater when maize was planted after wheat rather than clover. Total N %, organic matter and K% were higher after clover, but P% was slightly greater after wheat plantation. - All maize characters as well as grain yield were markedly enhanced when planting maize after soil preparation has been done using moldboard plowing + single chisel plowing. Meanwhile, this treatment was of the most effect in weed reduction. Moreover, total N%, organic matter, P% and K% were greater. - Studied maize characters were positively affected with increasing nitrogen application treatments. The best treatment for enriching soil fertility was 60 kg organic N +120 kg mineral N / fed. -Economic return Maize plantation preceded by clover using soil preparation by MBP + SCP and fertilized with 120 kg MN /feddan produced the highest grain yield and consequently the highest net farm return per year being 5687.09 and 6016.31 L.E./feddan in the first and the second years, respectively.