Under the background of China’s construction of a new development pattern and the continuous promotion of low-carbon economic strategy， green innovation becomes an important driving force to promote the optimization and upgrading of industrial structure， and the core way to achieve the goal of high-quality economic development. Based on the data of manufacturing companies listed on Shenzhen GEM of China from 2009 to 2021， it explored whether and how different types of technology alliances affect green innovation of start-ups. The results indicate that technology alliances between universities and research institutions enhance green innovation， mainly reflecting in the output of green invention patents， while technology alliances with peer enterprises is not conducive to green innovation of start-ups， which is specifically manifested in the decline of the output of green patent， green invention patents and green utility model patents. The moderating effect test shows that higher R&D intensity reduces the negative impact of inter-firm technology alliance on green innovation of start-ups， while strict environmental regulation not only weakens the negative effect of inter-firm technology alliance on green innovation of start-ups， but also amplify the positive impact of technology alliances between universities and research institutions on the execution of start-ups’ green innovation strategies. Further analysis finds that the two types of technology alliances have a certain mutually exclusive effect in the process of promoting the green innovation development of start-ups. Based on categorizing technology alliances into two dimensions based on member identity and functional heterogeneity， it analyzes deeply the effects of different types of technology alliances on firms’ green innovation， and also provides valuable insights for start-ups on how to choose technology alliance partners and build cooperative networks to advance their green innovation strategies.