Objectives Since individuals afflicted with cancer are at an elevated risk of dying by suicide, understanding suicide‐related ideation and behaviours is critical in identifying vulnerable patients. The interpersonal theory of suicide (IPTS) provides a framework to research risk factors for suicide and has been validated in different samples. The aim of this scoping review is to study literature related to IPTS and cancer patients. Methods This scoping review was registered with the OPEN Science Framework (osf.io/92465). The databases PsycINFO, Web of Science, PubMed and PubMed Central were searched. Eligible research needed to use a minimum of one psychometric element to measure at least one of the factors of the IPTS in individuals with cancer. Results Ninety‐six studies were identified and screened. Eligible research included individuals with cancer and the use of at least one measurement of at least one of the factors of the IPTS. Overall, four articles met the inclusion criteria and three studies found significant associations of components of the IPTS and suicidal ideation/behaviour. Conclusion While these initial findings support the notion that the IPTS is relevant for individuals with cancer as well, a direct validation of the IPTS in cancer patients is needed.