Clinical observation has revealed that depression and pain are common co-morbidities.However, experimental studies often report controversial results.With two animal models of depression, i.e., the unpredictable chronic mild stress (UCMS) and the olfactory bulbectomized (OB) models, we tested the modulation of depressive states on various pain tests and chronic pain models, including the radiant heat test, the hot plate test,the von Frey hair test, the Formalin test, and chronic pain models such as Freunds complete adjuvant inflammation model and spinal nerve ligation model.With all these models, we are able to describe that depression consistently induces hypoalgesia in animals with or without a chronic pain conditions, when tested with avoidable, external, or phasic pain.However, when tested with tonic, internal, or unavoidable pain like in the Formalin test, the animals with depressive emotional states displayed clear hyperalgesia.This is also true for animals experiencing both tonic and phasic pain, indicating that the depressive modulation of phasic and tonic pain may be via divergent pathways.Finally, we described that animals with remittent depression also displayed significantly enhanced response to Formalin injection.These results suggest that depression may have persistent modulation on the perception and response of pain.