PurposeAs a special psychological variable, illness perception significantly affects the cancer adaptions of colorectal cancer couples. No studies focus on facilitating cancer adaption by targeting the illness perception in colorectal cancer couples. This research attempted to explore the feasibility, acceptability, and potential effectiveness of an illness perception intervention program designed for couples with colorectal cancer, guided by a self-regulation common sense model. MethodsA single-group pilot study including pre- and post-testing was carried out with Chinese couples having colorectal cancer. Six sessions were delivered consecutively by researchers via in-person or telephone for couples. By calculating the rates of recruitment and retention, the feasibility of the intervention was analyzed. Intervention acceptability was evaluated by analysis of the post-intervention quantitative and qualitative data. Outcomes were described as illness perception, cancer-related communication problems, dyadic coping, quality of life, anxiety and depression, and benefit finding. Effect sizes were computed to assess the preliminary program effects. ResultsThe feasibility was confirmed by the recruitment (67.6%) and retention (82.6%) rates. The acceptability was endorsed by the reported participant satisfaction. Validating the program’s preliminary effectiveness, the intervention program has moderate effect sizes (Cohen’s d: 0.33-0.79) that boost illness perception and major cancer adjustment results for patients and their spousal caregivers. ConclusionsThe research proved that the couple-based illness perception intervention among colorectal couples was feasible, acceptable, and initially effective. To investigate this intervention program more thoroughly and apply it to a wider range of disease backgrounds, an extensive randomized controlled experiment is necessary.