We present a novel grid-based method for simulating multiple unmixable fluids moving and interacting.Unlike previous methods that can only represent the interface between two fluids (usually between liquid and gas), this method can handle an arbitrary number of fluids through multiple independent level sets coupled with a constrain condition.To capture the fluid surface more accurately, we extend the particle level set method to a multi-fluid version.It shares the advantages of the particle level set method, and has the ability to track the interfaces of multiple fluids.To handle the dynamic behavior of different fluids existing together, we use a multiphase fluid formulation based on a smooth weight function.