The invention discloses a video measuring tool based on a camera. The video measuring tool comprises a measuring tool body and the camera (2), wherein the camera (2) is used for shooting scale marks on a graduated scale body (1) to obtain a scale mark image, and the measuring tool body can be an extension scale, a sliding scale, a micrometer caliper and a universal angle meter. By the adoption of the video measuring tool, scale values can be shown accurately in a visualized mode through the scale mark image, reading of the scale values is achieved by shooting the scale mark image with the camera, errors caused by failures of electronic elements are eliminated, influences of temperature drift of the electronic elements can be avoided fundamentally, influences of failures of a temperature compensation circuit can be avoided, it is physical scale marks that are shot by the camera, neither the scale marks nor the camera can be affected by temperature drift, scale reading results are high in reliability, maintenance is easy, and cost is low. For special engineering projects, remote network monitoring of multiple tools to be measured can be achieved, monitoring efficiency is improved, and monitoring workload and cost are reduced.