This research highlights a multi-variety technique to examine the relationship between dependent and independent variable in predicting the water quality index in Manjung Rivers and its affluents. The model building process been used to analyse and generate the data. There are 63 possible models for single order multiple regressions. The number of possible model started to reduce as we started to eliminate insignificant variable. This model then needs to run under eight selection criteria to identify the best model. The best model will be certified by using Mean absolute percentage error (MAPE) in order to measure the validity of the model.