Acceptance of web based marketing information system has remained a topic of interest for a last few decades. Several theories, specifically over the conceptualisation of the technology acceptance model (TAM) have emerged and they have been applied in different contexts to investigate new insights into the acceptance behaviour at individual and organisational levels. The purpose of this paper is to determine whether a relationship exist between user satisfaction and acceptance of web based marketing information system (MKIs) among microfinance institutions in Nairobi Region, Kenya. Anonymous and self-administered questionnaires were distributed to 383 respondents. A total of 370 usable responses were received, resulting in a response rate of 96.6% which was considered satisfactory for subsequent analysis. Due to the quantitative nature of the study, the results are analysed with statistical measures. The results indicated that Satisfaction was influential determinant of acceptance with t= 5.1568, pvalue= 0.005 at 1% significant level. Theoretical contributions and practical implications of the findings are discussed and suggestions for future research are presented