Background: Several lines of evidence suggest that early sensory stimulation and regular family visiting programs are potential nursing interventions to improve the outcomes of head injured comatose patients. However, little is known about the impacts of family involvement in providing sensory stimulation. Objectives: To determine the effects of a sensory stimulation program conducted by nurses and families on the consciousness, level of cognitive function, and basic cognitive sensory recovery of head injury comatose patients. Patients and Methods: This was a randomized clinical trial performed at the Shiraz level I trauma center including 60 head injured comatose patients with an initial Glasgow coma score (GCS) of less than 8. Patients were randomly assigned to receive sensory stimulation by a qualified nurse (nurse group; n = 20), by the family (family group; n = 20), or usual care (control group; n = 20). The sensory stimulation program involving the nurses and patients’ families was conducted, twice daily, in the morning and evening for 7 days. The level of consciousness, level of cognitive function, and basic cognitive sensory recovery of the patients were evaluated and monitored using the GCS, Rancho Los Amigos (RLA), and Western Neuro-Sensory stimulation profile (WNSSP). Data were analyzed by chi square, Kruskal-Wallis, and repeated-measures tests using SPSS. Results: All the patients were comparable regarding their baseline characteristics, level of consciousness, level of cognitive function, and basic cognitive sensory recovery determined by GCS, RLA, and WNSSP. Although the two intervention groups of the study improved, those who received the sensory stimulation program from their families had significantly higher GCS (P = 0.001), RLA (P = 0.001), and WNSSP (P = 0.001) scores after 7 days when compared to the two other groups. Conclusions: The application of sensory stimulation by families led to significant increases in the consciousness, level of cognitive function, and basic cognitive sensory recovery of comatose patients with severe injuries.