Organizational success heavily relies on the competitiveness of products and services under rapidly changing market conditions. This enterprise competitiveness becomes more critical for project-based enterprises as modernization of the Chinese construction industry creates greater challenges and uncertainty in construction operations, which determines the sustainable advantages of enterprises to a certain degree. Traditional wisdom focuses on cost efficiency, asset differentiation, and service performance to gain competitive advantages. This paper explores the influence of organizational flexibility and organizational innovation on enterprise competitiveness for Chinese construction organizations. A designed structured questionnaire was developed and conducted targeting the project-based enterprises in China’s construction industry and is accompanied by a structural equation modeling analysis. Results indicate a positive impact of organizational flexibility on enterprise competitiveness along with a mediation role of organizational innovation. The study concludes that new organizational strategies are required for Chinese project-based enterprises to maintain enterprise competitiveness in order to realize the sustainable development of enterprises.