In the study of second and foreign language acquisition, errors have been investigated to discover the processes learners make use of in learning and using a language. Error Analysis has provided valuable information not only for teachers and learners but also for textbook compilers, syllabus designers and researchers. However, relatively few empirical studies have been conducted in investigating the errors made by Chinese learners in writing. The objective of this thesis is. therefore, to furnish some information in this area for pedagogical concern and further research.The thesis is composed of two parts: Part 1 examines the development of error studies -- from Contrastive Analysis (CA) to Error Analysis (EA). then to the theory of Interlanguage. The strength and weakness of the EA approach, in particular, are evaluated and its pedagogical significance discussed. Part 2 is a detailed report of an empirical study of writing errors conducted by the present writer within the framework of EA but with a corpus-based approach. Errors for analysis were obtained from classroom compositions written by third-year English majors at Xiamen University. Two areas of errors, namely text errors and discourse errors, are examined in the sequence of identification, description and explanation. Deviations from the standard norm are counted and categorized, and error causes explored and interpreted. It is discovered that local errors are less prevalent than global errors and that discourse errors and lexical errors represent two striking types of errors. Grammatical errors are found unexpectedly frequent. Many errors are caused by the interference of Chinese, but more are the result of the improper application of English rules.After the statistic analysis and error interpretation, proposals are made in pedagogy to improve the quality of the writing class and the effect of error treatment. The integration of the process approach and the product approach is recommended for teaching writing and specific advice given for dealing with errors of various types.It is hoped that the present thesis will help language teachers to identify the problems or weak areas of Chinese EFL learners in writing. It is also hoped that such findings and proposals will give some insights to material writers and syllabus designers when planning the course of English Writing.