Abstract: Study of some problems concerning granitic rocks in the Nanling region should be based on geological mapping so that unanimity of views can be reached. Taking for example the study of the Donegal batholith in North Ireland, the author points out that solid field geological work, particularly geological mapping, is indispensable for continuous progress in the study of granitic rocks in depth and breadth. He puts forward his views about Caledonian granitic rocks, HercynianIndosinian granitic rocks and late Yanshanian granitic rocks along the coast of Fujian and Guangdong as well as the relations between the formation of granites and the geological setting.