Background: Hand hygiene is a simple and low-cost practice to prevent the spread of many micro-organisms that cause healthcare-associated infections. Aim: This is a descriptive study designed to investigate the compliance of patient companions and visitors with hand hygiene. Methods: The study included 209 companions and visitors of patients hospitalized in a university hospital in the west of Turkey. A demographics and hand hygiene questionnaire and a hand hygiene practice observation form were used to acquire data. Findings: Of the patient companions and visitors, 96.2% stated that they did not receive training on the importance of handwashing during their stay in the hospital, and 74.6% stated that handwashing was very important in the prevention of diseases. The patient families reported that they most often washed their hands after touching bodily fluids (91.7%), and that they rarely washed their hands before touching a patient (34.0%). The rates were decreased in the observations; the lowest rate for handwashing was before touching a patient (22.4%) and the highest rate for handwashing was after the risk for contamination with body fluids of the patient (68.6%). Conclusion: The patient companions and visitors received no training on the importance of hand hygiene during the hospital stay, and the observed rate of compliance with hand hygiene was lower than stated. Recommendations include delivering planned handwashing training to patient companions and visitors using different teaching methods, and to conduct longer observational studies.