Firewood harvesting is a major threat to mangrove ecosystems in Solomon Islands. Improved cooking stoves could reduce firewood use and thereby ease pressure on mangroves. We conducted a field-based experiment in Langalanga Lagoon to evaluate this theory of change. Our results suggest that the so-called ‘kiko stove’, an improved cooking stove that is widely promoted in Solomon Islands, is not more efficient than cooking on an open fire in terms of cooking time and wood consumption. Yet, women who use the kiko stoves perceive a number of benefits and think the stoves reduce mangrove degradation. Promoting kiko stoves can transform gender norms that inhibit community-based resource management, and thereby provide a starting point for the conservation and rehabilitation of mangroves.