multiprocessor task scheduling is a NP-hard problem and Genetic algorithm (GA) has been revealed as an excellent technique for finding an optimal solution. In the past, several methods have been considered for the solution of this problem based on GAs. But, all these methods considers single criteria and in the present work, minimisation of the bi-criteria multiprocessor task scheduling problem has been considered which includes weighted sum of makespan & total completion time simultaneously. Efficiency and effectiveness of genetic algorithm can be achieved by optimization of its different parameters such as crossover, mutation, crossover probability, selection etc. The effects of GA parameters on minimization of bi-criteria fitness functi...