The study principally examined the determinants of net value added to produced and processed paddy rice in South east Nigeria It specifically, identified the socio-economic characteristics of the respondents, analyzed the determinants of net value added to produced and processed paddy rice as well as ascertained the constraints to processed and produced paddy rice. Multi-stage sampling technique involving purposive and random sampling methods was used to select 240 respondents. Primary data were collected on rain-fed production season using structured questionnaires administered to the respondents by personal interview. Descriptive statistics,, multiple regression and principal component analysis were used to analyze the data. Results obtained showed that gender distribution of the respondents was 63%males and 38% females. More respondents are between the ages of 41-50 and31-40 respectively and house hold size of 4-6 .Farming experience showed that 136 respondents representing 57% had engaged in the business between 11-20yrs.The results also showed that 67% of the respondents accessed farm credit while 25% did not.66% of the respondents belonged to farmers association while 75% were not visited by extension agents. Variables (age, gender, years in school, household size, years of experience, training/extension visits, costs incurred, value addition technique and market price) significantly influenced the net value added while marital status, membership of cooperative, and access to credit did not. Constraints to paddy producers and processors were accessibility to farm machine, poor infrastructure and scarcity/high cost of labor, low access to credit/grant; low proactive measures to flood and drought control; insufficient knowledge of agro-chemicals, and late provision of essential training and services; and processors: use of outdated rice milling machines, high cost of modern rice processing machines, low access to modern rice processing machineries and low acceptability of local rice. Recommendations include; establishment of farm machinery hiring centers for producers and supply of modern rice milling machines to rice processing clusters, development of dams and irrigable lands, training and re-training on access to fund, utilization of biodegradable wastes from paddy rice, proactive measures of flood and drainage control, adequate use of agro-chemicals, use of modem techniques, and involvement of National Agency for Food and Drug Administration and Control in quality control. Keywords: Agriculture, Paddy Rice, Value Addition, Nigeria.