OBJECTIVE: To test feasibility and preliminary efficacy of a couple-based supportive communication (CSC) intervention for head and neck cancer (HNC) delivered during patients' oncology treatment. METHODS: Twenty couples were randomly assigned to either a four-session CSC or a treatment-as-usual (TAU) condition. The CSC intervention primarily focused on increasing couple emotional disclosure, supportive listening, and social support. Patients and partners completed measures of individual and relationship functioning at baseline, post-intervention, and 6-month follow-up. RESULTS: Ninety-eight percent of CSC sessions were completed and couples reported high levels of satisfaction with the intervention. Between-group effect sizes indicated that patients and partners in CSC reported improvements in individual and relationship functioning, relative to those in the TAU condition. CONCLUSIONS: A couple-based communication intervention delivered during oncology treatment is feasible and acceptable in the context of HNC and may lead to improvements in individual and relationship functioning. Preliminary efficacy results are interpreted in the context of social-cognitive processing and intimacy theories. TRIAL REGISTRATION: The trial was registered on www.clinicaltrials.gov (NCT01785576) first posted on February 7, 2013.