ObjectiveTo overview the systematic reviews of the efficacy of cancer patient decision aids (PDAs) for treatment decision-making. MethodsThe PubMed, Web of Science, Cochrane Library, Embase, CINAHL, JBI, CNKI, VIP, CBM and WanFang Data databases were electronically searched to collect the systematic reviews relevant to the objective from inception to September 2023. Literature screening, data extraction, methodological quality assessment of the included literature, and summary and grading of the evidence were carried out independently by two researchers, and duplication of original studies in the included systematic evaluations was investigated using the corrected covered area (CCA). ResultsA total of 17 systematic reviews were included, of which 13 (76.47%) were low- or very low-quality studies. A total of 64 pieces of evidence were included, of which only 26 (40.62%) were of moderate quality, and the original studies included in the included literature had a low degree of overlap (CCA=0.05). The results of meta-analysis showed that PDAs could increase decision-related knowledge, reduce decision conflict and regret in cancer patients' treatment decision (P<0.05). However, there was no significant difference in decision satisfaction, anxiety or depression (P>0.05). ConclusionPDAs can improve cancer patients' knowledge related to treatment decision, reduce decision conflicts and regrets, and have no significant negative effects on decision preparation, satisfaction, anxiety, and depression. However, the existing systematic reviews are of low quality and limited to a few cancer types.