Purpose: Cognitive symptoms are reported to affect cancer survivors’ functioning at work. However, little is known about the type of cancer treatment and cognitive symptoms in working cancer survivors. We examined the longitudinal association between type of cancer treatment and cognitive symptoms in cancer survivors post return to work, and whether the course of cognitive symptoms over 18 months differed per type of cancer treatment. Methods: Data from the Dutch longitudinal “Work-Life after Cancer” study were used. The study population consisted of 330 working cancer survivors who completed questionnaires at baseline, and 6, 12, and 18 months follow-up. Cognitive symptoms were assessed with the cognitive symptom checklist-work and linked with cancer treatment data from the Netherlands Cancer Registry. Data were analyzed using generalized estimating equations. Results: Cancer survivors who received chemotherapy reported comparable memory symptom levels (b: − 2.3; 95% CI = − 7.1, 2.5) to those receiving locoregional treatment. Executive function symptom levels (b: − 4.1; 95% CI = − 7.8, − 0.4) were significantly lower for cancer survivors who received chemotherapy, compared with those receiving locoregional treatment. In cancer survivors who received other systemic therapy, memory (b: 0.4; 95% CI = 0.1, 0.7) and executive function symptom levels (b: 0.4; 95% CI = 0.0, 0.7) increased over time. In cancer survivors who received chemotherapy and locoregional treatment, memory and executive function symptom scores were persistent during the first 18 months after return to work. Conclusions: The contradictory finding that cancer patients receiving chemotherapy report fewer cognitive symptoms warrants further research. Implications for Cancer Survivors: Working cancer survivors may have cognitive symptom management needs irrespective of the type of cancer treatment they received.