Background Suicide survivors are prone to elevated risk for several psychiatric and somatic complications, including complicated grief (CG) and depression. Recent studies have highlighted the possibility of posttraumatic growth (PTG) among suicide survivors. However, to date, no longitudinal study has focused on the relationships between CG and PTG among suicide survivors. Aims In this 18-month longitudinal design study, our goal was to investigate the longitudinal bidirectional associations between PTG and CG, as well as between PTG and depression among suicide survivors. Method Participants were156 suicide-loss survivors, aged 18–70, who completed questionnaires tapping the CG and PTG at T1 and again after 18 months (T2). Depression was measured only at T2. Results The integrated model showed that CG-T1 predicts a reduction in PTG-T2 levels, beyond the trajectory of PTG. Whereas PTG-T1 was negatively correlated with CG-T2 and with depression at T2, this path was only marginally significant in the model.