Contemporary metaphor theory provides a platform for exploring the interface-integration of cognitive linguistics theory and second language acquisition, teaching and learning, in which Metaphorical Competence (MC) has been a focal issue of applied cognitive linguistics. Employing contemporary metaphor theory, this study is to probe into the influence of MC on the output-oriented writing ability among international students learning Chinese as a foreign language. The study first demonstrated through CiteSpace the current status of MC researches in foreign language teaching and education. Then, the study designed an experiment, which engaged an experimental group and a control group with randomly selected group members of comparable Chinese proficiency. The results show that: 1) Metaphorical competence and Chinese writing competence of international students are generally weak; 2) There is a positive correlation between metaphorical interpretation and production competence and writing competence, while the relationship between students' metaphorical identification competence and their writing competence is not significant; 3) Metaphor teaching can substantially improve students' Chinese writing and metaphorical competence. The above conclusions have implications for cultivating metaphorical awareness and competence of students of different linguistic backgrounds.