What may be the differences between Chinese and German usages of truth and modality? And, what disturbances on native Chinese learners of German may be aroused due to these differences? Present study aims to compare the differences between Chinese and German usages of modality. Mistakes of the translation work from Chinese into German of 60 subjects of German department were analyzed for investigation of Chinese disturbances in the learning of modality. Possible solutions are presented as references for teachers in achieving better learning effects.