AbstractPrecast concrete construction (PCC) is one of the most innovative and efficient methods in construction, but the separate processes involved in this method are one of its disadvantages. Therefore, the project owners considered quality management of PCC based on the Building information modelling (BIM) technique as a key factor to achieving desired tolerances, combining the separated process, and decreasing errors. This study was conducted to modify BIM processes based on dimensionless indices of PCC. The Fuzzy-decision-making trial and evaluation laboratory (DEMATEL) method was used to obtain the weight of variables. Genetic expression programming (GEP) was then used to estimate the modified BIM index (IMBIM) in the PCC according to other important indicators as input data. The statistical results comparing the predicted and calculated values of IMBIM show that there is a low root-mean-square-error (RMSE) of 0.027, low MAE of 0.019, and high R2 of 0.95 in the testing process. Thus, there is good agreement between the relationship of IMBIM and the calculated values that the proposed algorithm in this study can predict IMBIM with high accuracy. The sensitivity analysis illustrates that the index of system quality (Isq) has the most significant effect on IMBIM in comparison with other indices.