This study addresses a gap in understanding how small and medium-sized enterprises (SMEs) can effectively inspire their employees to adopt voluntary environmental behaviours, specifically aimed at mitigating climate change impacts on climate-threatened tourism destinations. Through smart PLS-SEM analysis of 437 valid responses from SME employees, an extended theoretical framework is developed, encompassing factors such as environmental Corporate Social Responsibility (CSR), sustainable intelligence, environmental empathy, environmental engagement, affective place attachment, and environmental citizenship behaviours. Findings reveal the direct relationship between enterprises’ environmental CSR practices and employees’ environmental citizenship behaviour. Mediating roles of empathy, engagement, and place attachment are identified in predicting employees’ voluntary pro-environmental behaviours in mitigating climate change impacts on destinations. The study also highlights the moderation effect of employees' occupations on the relationship between environmental engagement and pro-nature conservation behaviour. Implications are drawn for empowering SME employees’ environmental citizenship behaviour and promoting sustainable co-management of vulnerable tourism destinations facing climate change threats.