Start-ups with scarce resources and labor shortage need to come up with strategic responses to the lack of resources so as to enter and survive in the industries monopolized by large companies with high technical barriers. Now it is possible to find successful cases of small-sized companies to challenge existing companies due to rapid change of industry life cycle, and hence it is getting more important to have the capability to respond to changing business environment than to possess resources. This study aims to investigate how start-ups could enter and succeed in industries monopolized by large companies, and thus we focused on the case of MNtech Co. which has ranked No.1 in the optical film market share 10 years after entering the market monopolized by 3M. According to the study, we found that the monopoly market with high potential returns and high consumer needs could be rather favorable to the growth of firms in case they break through barriers to entry. We also found that startups need to accumulate production know how and increase their competency through co-production after accumulating sufficient capital by making a strategic retreat to enter the market as a sub-supplier rather than by making technology commercialization on their own so as to overcome their lack of resources and technologies. Consequently, it would become the basis for sustainable growth for start-ups to enter the market after acquiring know how and knowledge of process technology by a variety of strategic responses in the process of technology commercialization instead of dealing with all business by themselves to grow fast. Futhermore, to establish reliability by supplying to companies with high brand influence would play a important role in diversifying objects of supplies.