The research investigated the dynamics affecting the implementation of target costing in startups in Thailand. Startups face turbulent and competitive environments, lack of market demand and regulatory hurdles, which require effective cost management strategies. The study used quantitative methodology to evaluate the effect of various factors - perceived environmental uncertainty, competitor influence, product diversity, firm revenue, and business strategy for the adoption of target costing. Primary data from a sample of 314 respondents were used. The constructs validity and reliability were analyzed using Confirmatory Factor Analysis while Multiple regression analysis was used to evaluate the study hypotheses. The findings indicated that adoption of target costing was positively and significantly influenced by perceived environmental uncertainty, competitor influence, firm revenue, and business strategy, while product diversity has an insignificant influence. The study recommended that startup managers should consider using complex cost management techniques, as a means of acquiring competitive market advantage, strategic alignment of cost management and using competitors as a benchmark to evaluate their market competitiveness.