The symbiotic evolution of stakeholders within digital innovation ecosystems (DIES) is crucial for achieving ecological sustainability. Thus, we integrate the Lotka-Volterra symbiotic evolution model into digital DIES research by constructing both three-actor and four-actor dynamic interaction frameworks and simulating multiple symbiotic evolution scenarios. This study indicates that: (1) The principal actors in DIES are core digital enterprises, innovation partners, digital product users, and digital platforms, with their interdependencies governed by symbiotic coefficients. (2) Introducing the digital platform into the four-actor symbiotic model significantly increases the system’s maximum carrying capacity and equilibrium scale. Parasitic symbiosis and commensal symbiosis may temporarily enhance individual actors’ competitiveness, but they undermine the overall stability of cooperation, whereas mutually beneficial symbiosis provides the optimal pattern for system evolution. (3) Building on these insights, we propose a governance framework centered on resource balancing, value sharing, and trust cooperation, and demonstrate its practical applicability through an Alibaba Cloud case study. This work not only broadens the scope of symbiosis theory within a digital-economy context but also provides actionable guidance for designing efficient, resilient DIES.