Chronic pain can originate from injury or dysfunction in the peripheral nervous system, and currently available therapeutic methods are often ineffective. Despite the clinical significance, the mechanisms underlying the development and maintenance of chronic pain after peripheral nerve injury are obscure. During the last three decades, a number of animal models have been developed to study the chronic pain after peripheral nerve injury. Some of these animal models have been widely used in both academic research and pharmaceutical industry. The employment of animal models has greatly promoted our knowledge of the underlying mechanisms, suggested and tested new treatment strategies for chronic pain. This chapter reviewed the most important and widely used animal models of pain after peripheral nerve injury. Each of these animal models can produce a unique set of pain-related behavioral changes that are analogous to specific human chronic pain conditions. Improvements in the design and assessment of animal models will continue facilitating the research and treatment of chronic pain.