In the perspective of human ecology, Pranaji (2005) states that massive environmental damage due to the community’s ability to manage the environment is very weak, and it also indicates damage to cultural values. Pranaji’s reference in his research refers to Grootaert (1998) which states that the problem of socio-economic inequality (income distribution) and environmental damage is rooted in cultural values ​​and social capital in the local community. Departing from that thought, this study was conducted with the aim to 1) find out the income distribution or income gap among cassava farmers, 2) find solutions to efforts to increase cultural value in preventing environmental damage related to the agribusiness management of cassava in the Bengawan Solo Watershed Wonogiri District as indicated there was environmental damage to land degradation and erosion that led to the silting of the Wonogiri Reservoir. Survey approach of this research conducted with cross sectional data, with questionnaire research instruments. Data were analyzed by income analysis and income distribution analysis by finding the Gini Index value and illustrated by the Lorentz curve. The results showed that the level of income gap was quite high with the Gini Index reaching 0.4 in the agribusiness management of cassava. It is recommended to strengthen cultural values ​​through increasing the capacity of farmer in social empathy, the spirit of cooperation and appreciation for environmental knowledge and rational collective decision making and a high level of accountability in the agribusiness management of cassava while preventing environmental damage to the land.