Background and Objective: Hospitalization of a family member especially in the intensive care units (ICUs) is a crisis that can cause anxiety in the whole family. The present study was conducted to determine some effective factors that can lead to anxiety in families of patients hospitalized in Rasht ICUs in 2006. Materials and Methods: In this cross–sectional study 218 family members of 130 inpatients of Rasht Poorsina and Razi hospital ICUs were selected. Data were collected using researcher–made and hospital anxiety depression (HADS) questionnaires. Results: The results showed that the majority (77.1%) of patients’ family members were anxious. The anxiety odd ratio (OR) by logistic regression showed that anxiety rate increased with the decrease of patients’ consciousness level (OR= 9.726 per additional point), family members’ sex (OR= 6.171), making decision by family members (OR= 6.433) and older age (OR= 0.939 per additional year). Conclusion: The results confirmed the role of several important factors in inducing anxiety to the ICU inpatients’ families which require further consideration. These factors are recommended to be investigated upon admission and provide nursing care for preventing and overcoming anxiety in both patients and families.