Firefly algorithm (FA) is a new member of bionic swarm intelligence optimization algorithms. In this paper the bionic principle of FA is investigated and extended to solving a well-known NP-hard problem: Permutation Flow-Shop Scheduling Problem (PFSP). A corresponding solution strategy for PFSP bound is designed with its scheduling features. The strategy is implemented in experimentation on MATLAB workspace. At the end of the simulation, the experiment results verified that the effectiveness and feasibility offered by FA in solving the combinatorial PFSP optimization problems.