Abstract: This protocol describes steps for assessing anxiety-like behavior in rodents using an elevated plus maze test. The elevated plus maze (EPM) is one of the widely used behavioral assays to measure anxiety-like behaviors in rodents. In the EPM test, rats or mice are placed at the intersection of a plus-shaped maze with two open arms and two closed arms. The rodents show natural preference to stay in closed areas and avoid open and elevated areas. This expression of unconditioned anxiety is well captured in this assay.The amount of time spent in the open arm vs the closed arm is typically measured to assess anxiety-like behavior. The anxiolytic or anxiogenic effects of pharmacological agents and genetic manipulations can be investigated using this method.