Multilateration with laser tracker is an important method for on-site traceability in large-scale equipment manufacturing processes. An accurate evaluation of uncertainty is the key to ensuring quantitative accuracy in manufacturing processes. In this paper, we reported an accurate and fast technique for the evaluation of uncertainty in multilateration with laser tracker. First, the sources of uncertainty in multilateration were analyzed; these primarily include instrument errors, environmental conditions, and manufacturing errors of the target. Next, based on the propagation of uncertainty for multivariate measurement error models (GUM), the uncertainty in multilateration with laser tracker was estimated. Finally, the uncertainty in the point-to-point length was calculated. Our experiments reveal that the differences between the uncertainty values evaluated using GUM and Monte Carlo method (MCM) are within the numerical tolerance limit. The deviation in the uncertainty in coordinates is less than 0.000 2 mm, whereas that in the correlation value is less than 0.01. The time required for the GUM method is only 0.08% of the time required for the MCM method, and the value of En obtained from the point-to-point length test is less than 1. Thus, this study reveals that the evaluation of uncertainty in multilateration with laser tracker based on the GUM method is feasible and efficient, and the obtained results are accurate and reliable.