Legal frame work for the prevention of environmental degradation by oil and gas companies in Nigeria is partly Customary Law, partly Statutory Law, and partly Common Law. The Statutory legal regime for the prevention of environmental degradation in Nigeria is largely influenced by international legal norms for the prevention of environmental degradation by oil and gas companies. The legal frame work for the prevention of environmental degradation by oil and gas companies to a large extent produced institutional frame work prevention of environmental degradation by oil and gas companies. The Institutional frame work thus produced together with other institutions not produced by the legal frame work for the prevention of environmental degradation by oil and gas companies together enforce the legal frame work. Arising from the legislative response, there are catalogue of laws which seek to protect the environment from degradation by oil companies but unfortunately the laws are ineffective, in addition to the ineffectiveness of the laws, the laws are also not adequately implemented and enforced by the appropriate authority. It is also worrisome to note also that the laws are scattered in different legislation and other legal sources. This makes it difficult to get appropriate law to address a particular challenge. It is also sad to note that the environmental agencies lack specialized dedicated and courageous enforcement officers in enforcing the environmental laws. In addressing the short comings noted above, the study employed doctrinal and empirical approach applying both methods, the existing laws were carefully analyzed, institutions were visited and questionnaires were administered on host communities. Consequently, the study observed that, the laws and regulation that seek to prevent environmental degradation are generally weak, inadequate, short of administrative and enforcement machinery. The study also observed that there are too many institutions that regulate the affairs of the oil companies in Nigeria and these make their functions to overlap. The study further observed that the nature of the laws are scattered in different legislation and other legal sources. The study similarly revealed that the people of the Niger delta of Nigeria actually suffer from the operation of oil and gas companies. Consequently, the study made recommendations for the amendment of the policy and legal frame work, recommendation for the fusion of institutional frame work so as to have institution that enforces environmental law, employment of specialized, dedicated and courageous environmental law enforcement officers and establishment of environmental courts and more cooperation between host communities and oil operators.