For a country to deal with maritime terrorism as an offence it has to implement as provided under Article 3 of the SUA Convention and SUA Protocol, 1988 by incorporating it in its domestic law. However, since the amendment of SUA Convention and SUA Protocol which introduced the offence of maritime terrorism there was no amendment which was done to incorporate the offence in our domestic law. The legal regime of our country only allows prosecution of suspect if the offence has been domesticated into our laws. It investigates legal challenges at domestic level emanating from the international law. It also interrogates the adequacy and inadequacy of the existing legal framework in protecting maritime security. Aim of this research is to analyze the inadequacy of the existing Prevention of terrorism Act in prosecution of maritime terrorism towards the amendment of SUA Convention and its Protocol. After the consideration of the above issues the research finds that Tanzania lacks a comprehensive law which provide room for prosecution of maritime terrorism. Data was collected purposively from 29 respondents selected from Judges, Prosecutors. Advocates and Police Officers. Questionnaires and interview and documentary review were used to collect data. The major findings of this study revealed that in Tanzania legal regime does not provide room in prosecution of maritime terrorism as the country does not incorporate into our law Article 3 of the amended SUA convention which introduced maritime terrorism as an offence. Consequently, the research recommends a law reform in Tanzania especially the Prevention of Maritime Terrorism Act so as to incorporate maritime terrorism as an offence.