The invention discloses a transformer temperature rising device for realizing temperature difference at two ends of a winding. The transformer temperature rising device comprises a main body and heat source elements arranged on the main body, wherein the heat source elements are arranged at a transformer joint and are used for heating a transformer winding loop, and the main body is provided with a fixing module and a heat conduction module, wherein the fixing module is used for fixing the heat source elements on the transformer joint, and the heat conduction module is used for increasing a contact area between the heat source elements and the transformer joint. According to the device provided by the invention, externally-arrange heating devices are used to heat a transformer so as to make the temperature of the transformer rise, and therefore, temperature difference at the two ends of the winding can be realized without inner heat sources of the transformer required; since the temperature rise of the transformer does not require the inner heat sources of the transformer, so that the device of the invention can be applied to a transformer off-line test. The transformer temperature rising device has the advantages of high practicability and low cost, and will not cause destructive influences. The invention also provides a method for realizing the temperature difference at the two ends of the winding. The method is a nondestructive testing method and has high practicability in engineering and is suitable for being popularized in power grid companies and power users.