A handheld multi-parameter measuring instrument includes: a housing having a sidewall and opposed first and second surfaces, the sidewall, the first surface and the second surface cooperatively forming a cavity a cover attached to the sidewall and rotatably connected to the housing the blood oxygen transducer includes a light emitting unit and a light receiving unit the light emitting unit is configured to emit red light and infrared light alternately the light receiving unit is configured to receive the red light and the infrared light emitted from the light emitting unit the signal processing unit is received in the cavity of the housing and is configured to control the light emitting unit to emit the red light and the infrared light alternately the signal processing unit is further configured to calculate oxygen saturation based on a signal received by the light receiving unit the light emitting unit is located at a side of the cover attached to the housing, and the light receiving unit is located at the sidewall. When measuring blood oxygen saturation, one hand holds the first surface and the second surface of the housing, and one finger of the hand is inserted between the cover and the sidewall of the housing attached to the cover. This handheld multi-parameter measuring instrument is easy to use and has a high measuring accuracy.
