Background: It is widely accepted that pain is the most common complaint during invasive nursing procedures, which causes anxiety in patients. The purpose of this study was to determine the effect of family presence on the level of pain and anxiety of patients during invasive nursing procedures in emergency department.Methods: The present non-randomized controlled clinical trial was conducted on 70 patients referred to emergency department at selected hospital affiliated to Kermanshah University of Medical Sciences, Iran, in 2018, who were selected by convenience sampling method and then randomly assigned into two groups of intervention (even days) and control (odd days). The invasive nursing procedure was performed for the intervention group in the family presence for physical and psychological support and for the control group without the family presence. Data collection tools were the Spielberger State-Trait Anxiety Inventory (STAI) and the Visual Analogue Scale (VAS). SPSS version 23 software was used to compare the mean scores of pain and anxiety using independent t-test.Results: The mean pain score after the invasive procedure had no significant difference between the intervention group (3.9±1.5) and the control group (4.7±1.9) (P=0.073). In the intervention group, the mean score of anxiety after invasive procedure was significantly lower than before the invasive procedure (P=0.028), whereas the control group showed no change (P=0.556).Conclusion: The family presence during the invasive nursing procedures reduced the anxiety of patients but had no effect on their pain. Emergency nurses can take advantage of family presence during invasive procedures as a non-pharmacological intervention to reduce patients' anxiety.