Entrepreneurial factors that motivate people to establish firms are closely related to firms’ growth. This study analysed the relationship between growth of construction firms in Tanzania and factors that motivate their establishment. A survey to 227 Tanzanian construction firms was undertaken using a questionnaire. With the help of STATA 13.0 Software, data collected was analysed by using a multiple regression analysis. The findings indicate that only the business creation opportunity variable has positive and significant association with the growth of the firms studied, whereas knowledge-based resource and personality traits showed no significant impact. Provision of a link between groups of entrepreneurial motivation factors and growth of firms by supplying empirical evidence from Tanzania is one of the important inputs to the to the field of entrepreneurship.The indication that not all groups of entrepreneurial motivation factors have the same effects on growth of firms is another contribution of this study. Therefore, finding out how groups of entrepreneurial motivation factors affect firm’s growth is a contribution to the existing literature on entrepreneurship. This study also suggests that understanding the relationship between entrepreneurial motivation factors and firm’s growth is necessary for managers of construction firms as it informs them of the importance of creating a working environment that encourages proactivess and creativity at the workplace.