Ecotourism, which promotes environmental conservation and brings social and economic benefits through conscious and harmonious interactions between humans and nature, has become a principal tool for achieving these objectives. Sustainable tourism can only be supported with tourists realizing the elements of attraction toward ecotourism. This study analyzes the roots of ecotourism behavior using the Theory of Planned Behavior (TPB), specifically determining the roles of ecotourism tendency, attitude, human–land coordination stress, and sense of self-control in influencing tourists’ intention and behavior toward ecotourism. This study used a cross-sectional design, requiring 847 participants to complete a standardized questionnaire assessing their behavior toward ecotourism, attitudes, and perceptions. Reliability testing, descriptive statistics, regression analysis, and factor analysis were used to analyze the datasets to discover major factors relating to ecotourism intention behavior. A consequent outcome is that ecotourism attitude and self-determination are the significant drivers of ecotourism desire, while behavioral norms only impact ecotourism attitude and selflessness. The study concluded that the subjective perception of tourists and their behavior control ability are the ones that affect their ecotourism behavior more than other factors. The findings suggest that enhancing tourists’ ecotourism attitude, sense of self-control, and awareness of human–place coordination can significantly promote ecotourism behaviors. These results highlight the importance of comprehensive regional ecotourism analysis, robust environmental education, and promoting normative behaviors to foster sustainable tourism practices. To validate these findings, further research should focus on longitudinal studies and clinical trials to standardize integrated ecotourism strategies and explore the underlying mechanisms influencing ecotourism behavior.