Background <p>Sustained collaboration between basic science and clinical faculty in the Scholarship of Teaching and Learning (SoTL) remains challenging, partly because institutional incentives are often misaligned with the conditions required for cooperation.</p> Methods <p>We conducted a scenario-based discrete-choice experiment with 240 medical faculty members from four universities in China. The scenarios varied expected synergy, collaboration cost, inequity risk, direct reciprocity, and reputational visibility. We estimated logit models and mapped the results onto a behavioral game-theoretic threshold framework.</p> Results <p>Increased expected synergy, direct reciprocity, and reputational visibility raised willingness to collaborate, whereas higher cost and inequity risk reduced cooperation. In the pooled model, direct reciprocity showed the largest positive association with cooperation. Group comparisons indicated that clinical faculty were more responsive to direct reciprocity, whereas basic science faculty were more responsive to reputational visibility. In the calibrated threshold analysis, supportive mechanisms lowered the minimum expected synergy required for incentive-compatible cooperation, with reputational visibility showing a larger threshold reduction among basic science faculty and direct reciprocity showing a larger threshold reduction among clinical faculty.</p> Conclusions <p>Cross-group SoTL collaboration may be strengthened by institutional designs that combine credible reciprocity structures, visible recognition of educational scholarship, and fairness safeguards, while taking into account the different mechanism sensitivities of basic science and clinical faculty.</p>