This study examined the influence of green bond on environmental sustainability development in Nigeria, with specific reference to agencies and units under the Delta State Ministry of Environment. The study was necessitated by the growing concern over the environmental degradation in the country and the need to explore innovative financing tools such as green bonds that support eco-friendly development. The independent variables were Green Instrument Uptake, Sustainable Funding Allocation, and Regulatory Framework Strength, while the dependent variable was Environmental Sustainability Development. Thus, three hypotheses were postulated. A descriptive survey design was adopted, and the population comprised 1,392 staff across relevant environmental agencies in Delta State. Using Krejcie and Morgan's sample size table, 302 questionnaires were distributed, with 278 returned usable. Data were collected through a structured questionnaire, validated by experts and tested for reliability with a Cronbach’s Alpha value of 0.81. Data were analyzed using EViews 9.0, employing descriptive statistics, correlation, and multiple regression techniques. The findings revealed that Green Instrument Uptake had a negative but statistically insignificant effect on Environmental Sustainability Development (β = -0.131, p = 0.1281); Sustainable Funding Allocation showed a positive but statistically insignificant influence on Environmental Sustainability Development (β = 0.004, p = 0.9446); and Regulatory Framework Strength had a positive and statistically significant effect on Environmental Sustainability Development (β = 1.105, p = 0.0000). Based on these findings, it is recommended that government agencies enhance awareness and practical application of green instruments, improve transparency and timeliness in funding allocations, and reinforce regulatory frameworks. These measures are essential to ensuring that green bonds deliver tangible environmental benefits and contribute meaningfully to Nigeria’s long-term sustainable development agenda.