ABSTRACT: Urban geology relates to the application of geological studies to urban development. The role of geology in urban development cannot be over-emphasised. The development of urban centres and its associated problems are dictated by and large by the geologic settings of the areas concerned. In Malaysia, this is clearly illustrated by the major urban centres in the country, such as the capital city of Kuala Lumpur, Ipoh, Penang, Kuantan, Johor Baru and Kuching. This paper discusses and provides a comparative study of the urban geology of these six major urban centres in Malaysia. Kuala Lumpur and Ipoh provide good case studies on the influence of geology on urban construction and development. As both cities have rather similar geology with limestone as the dominant bedrock, construction problems and associated geohazards such as subsidence and sinkholes are strikingly similar indeed. In contrast, Penang is underlain by granitic rocks which form hilly terrains - thus it experiences marked landslide, rockfalls and other slope instability problems associated with hillside development. In the case of Kuantan where large areas are covered by basaltic soils forming low, undulating hills, landslide problems are minimal. Johor Baru, on the other hand, has the Old Alluvium as a unique soil deposit underlying much of the city and vicinities. The Old Alluvium forms mostly low-lying hillocks and has been sourced for construction fill materials. Finally, the East Malaysian city of Kuching lies on mainly flat, alluvial plains and peat swamps and has to contend with soft soil problems (consolidation settlement, etc.) and river-bank instability problems. Nevertheless, the few small hills in Kuching which are underlain by sedimentary rocks and river terrace deposits have been the subject of recent studies on slope instability/slope failures as water reservoirs or storage tanks are sited on these hills.