This study considers the application of genetic algorithm for scheduling of parallel batch processing machines with non-identical job sizes. Jobs have different sizes and release times. Firstly, we propose a mathematical programming model based on the hypothesis of the problem, and use BF and ERT-LPT to implement batch scheduling of jobs. Secondly, since the problem considered is NP-Hard, we design a new selection, crossover and mutation operation and solve it with genetic algorithm. Finally, the effectiveness of the algorithm through simulation experiments is verified.