A RESEARCH REPORT SUBMITTED IN FULFILLMENT FOR AWARD OF THE MASTERS OF BUSINESS ADMINISTRATION IN CORPORATE MANAGEMNET (MBA-CM) OF MZUMBE UNIVERSITY.Though, the direction of previous studies on Viral Marketing strongly addressed its spread and adoption in developing countries like Tanzania, the ecosystem of Viral Marketing that is relevant to developing countries like Tanzania is not yet known and developed. The general objective of this study was to assess the influence on the Viral Marketing on Sales; Perceptions of customers of Airtel Tanzania Ltd, Mwanza Branch. More specifically, the study identified the level of customers’ awareness on the Viral Marketing, Airtel strategies of Viral Marketing and analyzed the influence of Viral Marketing on sales. The study sample constituted by 68 Mzumbe evening class 2014 and 2015 Masters Students Mwanza Campus Airtel Customer and 8 Aritel staff. For combined respondents’ male representation was 51.3 percent while 48.7 percent was female The study found that, more than half Aitel customers awareness level of Awareness was above 80 percent Viral marketing has great opportunity to win the market, communication companies like Airtel need to set better Viral marketing plan that enable good customers service delivery, in order to capture attention of more customers from different location in Tanzania, particularly rural areas. Airtel need to focus on conducting more marketing research and further investigate needs of customers towards the use of Viral Marketing to influence retention and growth.