This study was performed at the Comarca Lagunera Region located between Durango and Coahuila States of Mexico. The main objective was to compare organic nitrogen mineralization and dsitribution over soil profile in different cow manure treatments in corn. This is a long term cow manure experiment started in 1998. The cow manure amounts studied as a first factor were 0, 40, 80, 120 and 160 ton per hectare and one additional control with nitrogen chemical fertilizer application of 150-100-0 Kg per hectare of nitrogen, phosphorus and potassium, respectively. As a second factor was crop with the levels of corn alone and corn-soybean associaton. The combination of factor give 12 treatments that were stablized in a complete randomized block design with a split block arranged replicated three times. Soil physical, chemical and plant parameters were measured to compare treatments. Such as soil temperature and moisture, nitrate, amonium, electric conductivity, organic mater etc. each 30 cm until 250 cm of depth. For plant the main variables measured were dry and moist forage and qulity. Results indicated statistical differences amoung treatments in almost all parameters and plant variables measured. The best treatment was 120 ton of cow manure application per hectare with 80 ton per hectare of corn-soybeen forage. Also this conbination had the best forage qulity but, farmers must be careful with soil concentration amount over time to avoid soil contamination. Nitrate and amonuim under drip irrigation system had not high concentartion in any cow manure treatments after 60 cm of depth.