The present invention relates to a complex granule formulation comprising a first granular part comprising levocetirizine or its pharmaceutically acceptable salt, cyclodextrin or its derivative, and an alkalinizing agent； and a second granular part comprising montelukast or its pharmaceutically acceptable salt, cyclodextrin or its derivative, and an alkalinizing agent. This formulation can effectively inhibit the production of related compounds of levocetirizine and montelukast by allowing levocetirizine and montelukast to form clathrate complexes with cyclodextrin, and using an alkalinizing agent. This formulation not only shows increased stability and bioavailability, but also improves patient compliance owing to its effective masking of bitter taste.
