Some important challenges of small businesses are limited financial resources, lack of experience in starting a business, and lack of business knowledge. A strategy to solve the challenge of small businesses is to use the capacity of large companies. Also, one of the emerging and new trends in the development of cooperation between small businesses and large companies is the use of the cooperation acceleration model. The present research was an applied study in goal and was conducted by a qualitative method based on grounded theory. The participants included 11 managers and professors who were knowledgeable in the field of business acceleration selected by purpose-based sampling until reaching theoretical saturation. To validate the findings, the raw text of the interviews was reviewed by an external observer with expertise in qualitative grounded theory research to determine the similarity of the extracted themes. The results indicated that the categories (strategic goals and definition of a joint cooperation roadmap, formulation of cooperation models and strategies, agility of procurement and legal processes, appointment of corporate mentors, gradual experimental process, testing, and cooperation partnership) would accelerate cooperation. The main contribution of the research is to provide a practical and market-oriented model of cooperation between small businesses and large companies in the ecosystem of entrepreneurship whose application will contribute to developing entrepreneurship and economic growth in society.