Language learning is a complex process, which involves many factors. Such factors refer to both the cognitive and affect sides. Recently more and more researchers realize that affect in language learning is so important, because attention to affect aspects can lead to more effective learning [1]. Most studies indicate that positive affects can facilitate language learning, while negative affects will generally, if not necessarily, bring about negative effects on a language learner, hence, will, of course, impede the learning efficiency. Of all the positive and negative affects, such as, happiness, excitement, anger, fear, disgust, etc, one becomes the focus of studies, that is, anxiety. It is thought that anxiety is one of the top factors influencing language learning whether in formal or informal settings. This essay tries to make analyses on the causes and influence of negative anxiety. And it also provides some suggestions to teachers and students for diminishing the negative anxiety so that foreign language learning can be effective.