This research amied mainly to identify knowledge level of extension workers with some technology which reducing use of the chemical fertilizers for fieldcrops in Kafr El-Sheikh Govemorate and studying the variables affecting the knowledge level of the respondents. Data were collected from 268 respondents chosen randomly from five districts in Kafr El-Sheikh Govemorate i.e.,: fowa, Motobus, Elriyed, Kallen and Biella district. Sample presenting 50% of total number of the extensionsts in the five districts mentioned during janury 2006 by using a personal interviewing questionnaire. Frequenoes, Percentage, Simple correlation, Anova, regression, and step- wise multiple regression techniques were used for data analysis. The most important results ofthis study revealed that: 1- Knowledge level of respondents were low regarding the four branch studied technology which were bio fertilizers, soil analysis, compost and amonia Gas fertilizer anoly about 7.5%, 3.8%, 12.8%, 6.8% of respondents had high knowledge levels in these technology, respectively. 2- General knowledge level of respondents was low concerning some technology of reducing the use of chemical fertilizers in field crops about 7.5% only of respondents had high knowledge level. 3- There is apositive and significant correlation relationship at the level of 0.01 of significancy between knowledge degrees of the respondents with some technology reducing the chemical use of fertilizers in the field crops. the following independent variables: educational qualification. educational specialization, size of farmland, extension work experience, agricultural experience, agricultural trainging extension training, soil field training, agricultural private business. job satisfaction. and exposure to communication channels. 4- There were six independent variables together explained about 49.5% of total variance in respondent knowledge degrees of four studied technology they were: agnwttural private business (31%), educational qualification (13.4%), soil field training (2%), job satisfaction (1 .4%), educational specialization (0.9%), and exposure to communication channels (0.8%).