When using theodolite and laser tracker for collaborative measurement, it is necessary to convert the measurement datum of different measurement systems. The traditional method of datum conversion is cumbersome and time-consuming. To solve this problem, this paper proposes a new portable reference conversion standard board, which is composed of a reference conversion component, a steering component and a tripod. The reference conversion is realized through the coordinate system constructed by the measuring target on the reference plate and the cubic mirror. When the laser tracker is used to verify the average position deviation of the standard board in different attitudes, the result is less than 0.01 mm, when the reference conversion standard board is used to verify the measurement deviation of the center point of the positioning hole of the theodolite system, the result is less than 0.06 mm, and the average absolute deviation of the normal vector of the cube mirror is less than 0.0043 °.The operation of the standard board is convenient and fast, which can meet the needs of benchmark conversion of theodolite and laser tracker collaborative testing under various working conditions, and has the value of application and promotion.