Objective To explore the trajectories of quality of working life (QWL) and fear of progression (FoP) in patients with hematologic malignancies after return to work, to examine their reciprocal predictive relationships, and to provide references for identifying critical time points and developing interventions for QWL and FoP. Methods A convenience sample of 256 patients with hematologic malignancies from two Grade A tertiary hospitals in Shandong Province was surveyed using the Quality of Working Life Questionnaire for Cancer Survivors (QWLQ-CS), and the Fear of Progression Questionnaire-Short Form (FoP-Q-SF) at 1, 4, and 7 months after returning to work. Data were analyzed using a cross-lagged model and a parallel process latent growth model. Results After returning to work, patients′ QWL showed a linear increasing trend, while FoP showed a linear decreasing trend. Across the three timepoints, the QWL level at the previous time point negatively predicted the FoP level at the subsequent time point (all P<0.05). The initial level of FoP negatively predicted both the initial level of QWL and its rate of increase (all P<0.05). Conclusion For patients with hematologic malignancies who have returned to work, QWL can predict subsequent FoP. Furthermore, both the "initial level" and the "rate of change" of FoP may impact the improvement of QWL. It is recommended to implement active interventions aimed at reducing the initial level of FoP and accelerating its decline, thereby enhancing patients′ QWL and ensuring their successful reintegration into work and society.