Dissertation (MSc Telecommunications Engineering)The study aimed at investigating and proposing the effective measures of using Central Equipment Identity Register to mitigate mobile phone theft over Airtel network operator as a case study in Tanzania. The study was conducted in Mbeya municipal. The study employed purposive sampling technique. Ninety respondents were involved where, eighty seven Airtel customers were selected randomly who live in Mbeya municipal and three key informants from Airtel (two site engineers and one network engineer) were interviewed using a check list in appendix 2. The specific criterion for selecting respondents was base on, being Airtel customers who were living in Mbeya. The study found that most of Airtel respondents didn’t have any knowledge on how to access their mobile phone identity numbers (IMEI) and how to safeguard their mobile phone from theft. The researcher recommends an effective campaign for mobile operators to educate their customers on the usage of mobile phone security features. Customers’ knowledge on the IMEI will enable the operators to combat mobile phone theft. However, the study found that an effective way of reducing mobile phone thefts for mobile operators in Tanzania is by using the CEIR which will enable the blacklisting the IMEIs of all the reported stolen mobile phones and blocking their use in all mobile operators in Tanzania. The effectiveness of CEIR will depend upon a combination of a technical solution, active cooperation and the partnership of the local police or law enforcement agencies, and an effective campaign to educate the mobile handset users.