Objective Because of the poor prognosis of ovarian cancer and concomitant distress, understanding contributors to positive well‐being is critical. This study examines spiritual growth as a domain of posttraumatic growth and its contribution to longitudinal emotional outcomes in ovarian cancer. Methods Ovarian cancer patients (N = 241) completed measures assessing spirituality (Functional Assessment of Chronic Illness Therapy–Spiritual Well‐being−12; subscales: faith, meaning, and peace), depression (Center for Epidemiologic Studies Depression Scale), cancer‐specific anxiety (Impact of Event Scale), and total mood disturbance (TMD; Profile of Mood States) prior to surgery and 1‐year postsurgery. Stressful life events in the year after diagnosis were measured at 1‐year postsurgery. Regressions examined the association between changes in spirituality and depression, anxiety, and TMD at 1‐year postsurgery. Additionally, spiritual change was examined as a moderator of the effect of recent life events on mood. Results Increases in peace were related to lower depression (β = −.40, P < .001), anxiety (β = −.20, P = .004), and TMD (β = −.41, P < .001) at 1 year. Changes in meaning and faith were unrelated to all outcomes. Additionally, changes in peace moderated the effect of stressful life events on depression (β = −.14, P = .027), anxiety (β = −.16, P = .05), and TMD (β = −.17, P = .01), such that those with a high number of life events paired with a decrease in peace experienced the worst psychological outcomes at 1 year. Conclusion These findings suggest that the quality of peace may be the most adaptive facet of spiritual growth in cancer patients. Furthermore, changes in peace appear to moderate the effect of life events on psychological well‐being.