The study analyzed the socio-economic determinants of organic manuring practices by farmers in Southern Agricultural Zone of Nasarawa state, Nigeria. The specific objectives were to: describe the socio-economic characteristics of respondents in the area; identify the type of organic manure used by the respondents; determine the effect of socio-economic characteristics on the use of organic manure. A multi-stage sampling technique was used in the selection of samples for the study. Fifteen farmers from each of the six selected villages were purposively selected on the basis of their use of organic manure for a total of 90 respondents for the study. Data were obtained from primary sources. The primary source was by personal interview and discussion using structured questionnaire. Descriptive statistics and multiple linear regression model was used to analyze data collected for this research. The first, second and fourth objectives were achieved using simple descriptive statistics such as frequency, percent and mean, while the third objective was achieved using multiple linear regression analysis. The study revealed that majority or 61.1% of the respondents were in the age bracket of 20-39 years old, which indicates that they were young and active who could engage in organic manure practices. The result on the type of organic manure indicated that cattle dung and green manure representing 48.9% and 38.9% were the major source of manure used by the respondents. The result of socio-economic determinant further revealed that about 69% of the variation in use of organic manure, while the significant determinants were age and membership of cooperative society both at 10% and 5% respectively. Therefore, the study recommend that Enlightenment campaigns should be done through change agents to sensitize farmers in the study area about the benefit of using organic manure for crop production as this will improve farmer’s attitude towards the adoption of sustainable land management practices.