We propose an automated software engineering approach, called task-based conceptual graphs (TBCG), to solving the university timetabling problem. Task-based conceptual graphs provides the automation of software development processes including specification acquisition, verification, and automatic programming. Modification can be directly performed on the specifications rather than on the source code, moreover, hard and soft constraints can be easily inserted or removed. Hence, our approach offers a certain degree of flexibility to support changes. A university timetabling system in the Department of Computer Science and Information Engineering at National Central University is used as an illustrative example for the proposed approach.