Objective <p>This study aimed to examine the dyadic effects of locus of control and coping style on the posttraumatic growth(PTG) of gynecological cancer patients and their spouses via the actor-partner interdependence model (APIM).</p> Methods <p>This was a prospective cross-sectional survey study. A convenience sampling method was used to select participants. The Demographic and Cancer-related Information Questionnaire, Internality, Powerful others and Chance Scale, Simplified Coping Style Questionnaire and Chinese-Posttraumatic Growth Inventory Scale were utilized for the survey. An actor‒partner interdependence model was constructed to examine the impact of locus of control and coping style on PTG for both patients and their spouses.</p> Results <p>The date of 400 individuals(200 couples) were analyzed. The PTG scores for patients and their husbands were 61.66 ± 12.82 and 57.77 ± 12.03, respectively. Both partners' PTG was influenced by internal locus of control and positive coping style <i>(P</i> &lt; 0.01). Each partner's internal locus of control and positive coping style could predict their own PTG, with a significant actor effect (<i>P</i> &lt; 0.05). The spouse's internal locus of control could predict the patient's PTG, whereas the patient's positive coping style could predict the spouse's PTG, indicating significant partner effects (<i>P</i> &lt; 0.05).</p> Conclusions <p>The PTG of gynecological cancer patients and their spouses is moderate. The locus of control and coping style of both partners have an interactive effect on their own PTG. To promote PTG for both partners, healthcare professionals should intervene simultaneously with patients and their spouses, incorporating positive psychological intervention methods.</p>