Platform ecosystems contain massive yet fragmented innovation resources.How entrepreneurial complementary firms integrate and internalize these resources under conditions of scarcity to drive collaborative innovation requires further exploration.Drawing on the theory of dynamic capabilities and ecosystem governance,this paper constructed a mechanism model to investigate how the platform ecosystem capabilities of complementary firms influence collaborative innovation behaviors,with a focus on the mediating role of entrepreneurial culture and the moderating role of resource bricolage.Using a dataset of 310 survey responses from platform-based complementary firms,the study conducted an empirical testing through multiple regression and bootstrap sampling methods.The findings revealed that:(1)The platform ecosystem capabilities of complementary firms effectively drive collaborative innovation by integrating and reconfiguring resources from ecosystem leaders or platform networks;(2)Entrepre-neurial culture characterized by continuous change and opportunity-seeking partially mediates this relationship;and(3)Re-source bricolage enhances the adaptability of complementary firms under resource constraints and promotes sustained collaborative innovation as a moderating mechanism.This study will provide theoretical foundations and practical insights for resource govern-ance,cultural shaping,and innovation entrepreneurship incentives within platform ecosystems.