A terminal and electrical water-resistance method, the terminal includes: a circuit board, a battery and a housing, wherein the battery provides a power source for the circuit board, the housing is provided with a transparent medium used for reflecting light and the circuit board includes: a detection module, a control module and a power-off switch, wherein the detection module is configured to: emit light towards the transparent medium, and receive the light reflected by the transparent medium, convert the light into electric signal data and send the electric signal data to the control module; the control module is configured to: after receiving the electric signal data, compare the electric signal data with preset data and trigger the power-off switch when a difference value between the electric signal data and the preset data reaches a preset threshold, wherein, the preset data are electric signal data when the light is totally reflected by the transparent medium, and the preset threshold is preset accordi
