Auditory-verbal training is essential for children with hearing challenges, and the gamification approach has become a promising direction for improving the rehabilitation experience and effect. However, the specific influence of the gamified training approach on participants at different rehabilitation stages has not been empirically studied. This paper is thusly intended to investigate the research questions: Do the training performances of children at advanced rehabilitation stage differ before and after using the gamified training system? Do the training performances of children at intermediate rehabilitation stage differ before and after using the gamified training system? Do children enjoy the gamified training approach? For the purpose, a digital gamified auditory-verbal training system was originally developed, and a series of user experiments were organized. Particularly, 31 hearing-challenged children aging between three-six years old at an auditory-verbal rehabilitation center were recruited to take the training, and six professional therapists were also invited to assist with the experiments and attend the interviews. Based on the training performance observation and interviews with participants, their parents and the therapists, it can be found that generally the gamified training approach can effectively facilitate the training experience, and help with the basic auditory memory and expression capabilities. Regarding the specific influence, the gamified way can better improve the basic auditory-verbal performance of children at the intermediate stage, since they focus more on the ease of learning and adaption to the training system. These findings and conclusions can provide insights for the further exploration and application of the gamification approach in children's auditory-verbal rehabilitation.