This paper studies the hybrid flow shop scheduling where the optimization criterion is the minimization of total tardiness. First, the problem is formulated as a mixed integer linear programming model. Then, to solve large problem sizes, an artificial immune algorithm hybridized with a simple local search in form of simulated annealing is proposed. Two experiments are carried out to evaluate the model and the algorithm. In the first one, the general performance of the model and the proposed algorithm is experimented. In the next one, the presented algorithm is compared against some other algorithms. The results support high performance of the proposed algorithm.