An oil resistance test method for an electronic device, with at least one type of resin material provided on at least a portion of an outer surface of the electronic device, the oil resistance test method comprising: setting a test temperature; immersing the electronic device in a water-soluble cutting oil in an atmosphere of the test temperature, the cutting oil containing a mineral oil and a surfactant and exhibiting a milky-white appearance when diluted with water; and determining, based on an electrical characteristic of the electronic device, whether or not the electronic device has been degraded by the cutting oil, wherein determining whether or not the electronic device has been degraded includes: determining whether or not an insulation resistance value of the electronic device has become equal to or less than a reference value, or measuring an electrical characteristic of the electronic device in an energized state; characterized in that the method further comprises: estimating, based on a total immersion time of the electronic device in the cutting oil until degradation of the electronic device is detected, a life of the electronic device with respect to oil resistance, wherein an estimated value of the life is calculated by multiplying the total immersion time by a predetermined acceleration factor, and wherein the acceleration factor is calculated, using first and second electronic devices of an identical design, by a ratio between a time until the first electronic device is degraded in an actual use environment, and a total immersion time of the second electronic device in the cutting oil until the second electronic device is degraded at a part identical to a degraded part of the first electronic device in the atmosphere of the test temperature. setting a test temperature; immersing the electronic device in a water-soluble cutting oil in an atmosphere of the test temperature, the cutting oil containing a mineral oil and a surfactant and exhibiting a milky-white appearance when diluted with water; and determining, based on an electrical characteristic of the electronic device, whether or not the electronic device has been degraded by the cutting oil, wherein determining whether or not the electronic device has been degraded includes: determining whether or not an insulation resistance value of the electronic device has become equal to or less than a reference value, or measuring an electrical characteristic of the electronic device in an energized state; determining whether or not an insulation resistance value of the electronic device has become equal to or less than a reference value, or measuring an electrical characteristic of the electronic device in an energized state; characterized in that the method further comprises: estimating, based on a total immersion time of the electronic device in the cutting oil until degradation of the electronic device is detected, a life of the electronic device with respect to oil resistance, wherein an estimated value of the life is calculated by multiplying the total immersion time by a predetermined acceleration factor, and wherein the acceleration factor is calculated, using first and second electronic devices of an identical design, by a ratio between a time until the first electronic device is degraded in an actual use environment, and a total immersion time of the second electronic device in the cutting oil until the second electronic device is degraded at a part identical to a degraded part of the first electronic device in the atmosphere of the test temperature. estimating, based on a total immersion time of the electronic device in the cutting oil until degradation of the electronic device is detected, a life of the electronic device with respect to oil resistance, wherein an estimated value of the life is calculated by multiplying the total immersion time by a predetermined acceleration factor, and wherein the acceleration factor is calculated, using first and second electronic devices of an identical design, by a ratio between a time until the first electronic device is degraded in an actual use environment, and a total immersion time of the second electronic device in the cutting oil until the second electronic device is degraded at a part identical to a degraded part of the first electronic device in the atmosphere of the test temperature.