The study assessed awareness on corporate social responsibility (CSR)practice based on selected companies in Mwanza City. CSR is argued to create social development in the community but little is known on its extent in the awareness of CSR practice related to social-economic development among companies in Tanzania. Accordingly, the study advanced three specific research objectives, namely (i) to assess whether CSR initiatives were undertaken by selected companies in Mwanza city (ii) to identify any benefit gained among selected companiesafter practicing CSR in Mwanza City and (iii) To assess factors influencing CSR implementation among selected companies in Mwanza City.Corporate Accountability Theory (CAT) was used to underpin the study. The study employed qualitative research approach-a case study design where each selected company was consideredas a separate case. Purposive samplingwas used to select companies participating in CSR and one manager responsible for CSR activities were interviewed usingsemi structured interview. Data collected were transcribed, coded, and analyzed in themes. The findings revealed that education, health projects, and games project were among the most CSR practice that contribute to the development of community and organization. Projects such as clean water supply, maintenance of infrastructure, and sanitation were least implemented under CSR. Among the benefitidentified by companies is company acceptance in the community, positive goodwill, and good relationship. Finally, the study found varied factors that influenced the practice of CSR to include increased customer base, gaining competitive advantage, instilling the culture of loving the company, and supporting the government to meet its objectives. The study concluded that companies are aware about CSR even though not all companies are involved in CSR practice.