Two field experiments were performed at the Experimental Station, Faculty of Agriculture, MansouraUniversity, during the two successive summer seasons of 2006 and 2007. The main objectives of this study were to determine the effect of organic fertilization (compost) doses, plant population (hill spacing) and nitrogen fertilizer levels on growth, yield and its components of maize (Zea mays L.) Single Cross Hybrid Pioneer 30 K 9 (S.C.H.P. 30 K 9). A strip split plot design with four replicates was used. The obvious results of this investigation can be summarized as follows: All studied characters were significantly improved by applying organic fertilization (compost) doses in both seasons.highest values of maize growth and productivity parameters were obtained by the application of organic fertilization(compost)at 4t/fed in both seasons. Increasing plant spacings up to 30 cm between hills (20 000 plant/fed) increased all studied characters, except number of days from sowing to 50 % tasseling and plant height, which increased due to sowing maize in hills 20 cm apart (30 000 plants/fed) in both seasons. Sowing maize plants in hills 25 cm apart (medium space i.e. 24 000 plants/fed) surpassed other plant spacings in grain yield (ardab/fed) in both seasons. Application nitrogen fertilization at the level of 125 kg N/fed significantly exceeded other studied levels (50, 75 and 100 kg N/fed) with respect to their effect on all the studied growth parameters and yield components as well as grain yield of maize in both seasons. Generally, it can be concluded that according to the obtained results from this study, sowing maize Single Cross Hybrid Pioneer 30 K 9 plants at 25 cm space between hills (24 000 plant/fed) and adding 4 t/fed compost as well as 100 or 125 kg N/fed can be consider the best treatment for raising maize productivity under the environmental conditions of El-Mansoura region.