A hand-held lens surface power measuring device is provided, which includes a main control cavity (2) and an optical measuring head (7). The main control cavity (2) includes a data-and-image processing control unit and a display screen (1). The main control cavity is fixedly connected with the optical measuring head. The optical measuring head includes a light source (15), prisms, a lens (9), a beam splitter (14), a ring-shaped aperture (17), an image sensor (10) and a lens support (3). The image sensor, the ring-shaped aperture and the beam splitter are sequentially distributed on the optical measuring head from top to bottom. The hand-held lens surface power measuring device measures the power of the lens surface on the basis of an optical reflection method, and the lens is not necessary to be de-blocked when the Rx lens are measured. The size of the device can be greatly reduced by adopting the optical measuring head with a single integrated structure, the device can be operated by a single hand of an operator, the installment and alignment of the optical measuring head is finished during implementing the optical contact or gluing, the subsequent alignment and maintenance are not required, a complicated alignment mechanism is saved, and the stability and the reliability of the device are improved.