Dissertation (MA International Relations)This scientific task was conducted in Mtwara Region, with the intent of determining illegal migrants‘ impact on land resources since Tanzania is increasingly and incessantly in receipt of migrants from bordering countries and beyond. Some outsiders unceasingly come in quest of impermanent stay whereas others have advanced lastingly. Even though some have done so in accord with related laws, others have penetrated and inhabited the country without observing the apt legal prerequisites. A model of 180 respondents was used and these were by chance obtained from Southern region of Tanzania. The methods used in data collection are interviews, questionnaire, documentary review and focus group discussion. Statistical Package for Social Sciences Version 16 and Analytical tools used were Likert Scale Weighting In this study the theories pertaining to Land Resources were cross tabulated to produce percentage and frequencies of the respondents on performance variable which makes acquainted the reader with paradigms, frameworks and approaches in the field of land resources. The study finds that there was absolutely a total understanding on illegal immigrants in Tanzania but the authorities are horribly rotten and irresponsible and the governmental institutions are profoundly corrupt. The land as fundamentally significant natural resources for the future generation is invaded and grabbed by immigrants without any reaction and legal measures on behalf of Tanzania Government. This situation is also perpendicular to lack of funds and political compliance which contributes to the poor technology, inadequate number of workers and insufficient working equipment. The study also unveils that there is a pathetic safety determination in the country borders, corruption and many absorbent ways which pilot to the invasion of illegal migrants in the Southern Region of Tanzania, Mtwara in particular. The study recommends that so as to guarantee the competence and adequacy in protecting the land resources as rare natural resources from being grabbed by illegal foreigners, thus, there is a need to better the pledge of the authorities more than ever and the government agencies and the inhabitants must vigorously be vigilant on this socio-economical calamity and national disaster for the future generation or children.