In class,Chinese learners can complete learning tasks under the guidance of teachers.Outside the classroom,they can independently complete learning tasks under the guidance of mobile APP,and this process is the process of informal Chinese learning based on mobile APP.In the era of smart phone,mobile APP has become an important tool in life.In terms of Chinese learning,Chinese learners have started to use mobile APPs to learn Chinese,and the combination of mobile APPs and informal Chinese learning has become an inevitable trend.The study of this new form of learning has some implications for Chinese learning,Chinese teaching and even Chinese international popularizing.In this paper,the study of informal Chinese learning based on mobile APP is mainly divided into three parts: learning content analysis,questionnaire survey,thinking and Suggestions.In the part of learning content analysis,the author observes the learning and training methods of Chinese learners by analyzing various learning contents.Through the questionnaire survey,the author found that in the informal Chinese learning based on mobile APP,the learning effect of pronunciation,vocabulary and Chinese characters is good,while that of grammar is not.The advantages of informal Chinese learning based on mobile APP can be summarized as the location is not restricted,the atmosphere is loose and the supplement is good.The shortcomings can be summarized as the imperfect knowledge system,the different quality of learning content,the low degree of matching with the textbook and the lack of practice.In addition,the author also puts forward some suggestions for the improvement of informal Chinese learning based on mobile APP.