The main purpose of this study was to find the optimal dyeing conditions as well as predict the colour strength (CS) of viscose/lycra blended knitted fabrics using Taguchi method. The controllable factors such as dye concentration, temperature, time, alkali concentration, salt concentration and liquor ratio have been used as input variables and CS of the fabric as response variable for the construction of Taguchi model. An L25 orthogonal array design has been chosen and conducted 25 experiments with three runs for each experiment. The optimal parameters in the dyeing process have been identified as dye concentration 9%, time 60 min, temperature 75 °C, salt concentration 50 g/l, alkali concentration 14 g/l and liquor ratio 1:8. Taguchi mathematical model built in this study has been confirmed by confirmation experiment as well as unseen experimental data. The mean absolute error and coefficient of determination (R2) were found to be 3.48% and 0.88, respectively, from the actual and predicted CS. It is concluded that Taguchi method is efficient on the optimisation and prediction of fabric CS in non-linear complex dyeing.