Eventhough Micro and Small Enterprises sector play great role in the economy through economic diversification, employment creation, generation and distribution of income and poverty alleviation, their current status of growth and development is insignificant because most MSEs are not growing and faced with the threat of failure due to many factors. In order to make the MSE sector the engine of economic growth and reduce the problem of unemployment, it is important to understand these factors determine growth of MSEs in different dimension. The main objective of this study is to assess the factors affecting the growth of micro and small enterprises (MSEs) in Awi zone of Amhara national Regional state. The study employed both descriptive statistics and econometric methods to analyze data collected from 356 sample operator or owner of Micro and small enterprises (MSEs). Under the descriptive statistics, frequency percentages, Mean and standard deviation and on the Econometrics side the Ordinary Least Square multiple linear regression model (OLS) are used. The findings of the study reveal that MSEs affected by lots of internal factors and external factors. From the internal factors the educational level of operators/owners, enterprise age and prior work experience of owner has significant effect on the growth of MSEs. The external factors including access to valuable training, access to finance, initial capital and the sector that enterprise engaged in has also significant effect on the growth of MSEs. Limited market access and facilities are also another important factor that affects the growth of MSEs in the study area. Thus, it is important that government bodies and NGOs together with financial institutions and development practitioner enact in line that promote the growth of MSEs through providing valuable and practical training, and sufficient financial support by providing better credit access. Key Words : Micro and Small Enterprise, Growth, Factors