Technical solutions for evaluating traditional English teaching composition and other problems, such as excessive subjectivity, waste of time, slow feedback, short scoring time, heavy tasks and so on. This paper first analyzes the theoretical basis of neural network algorithm, and completes the preprocessing of the composition text submitted by students from three aspects: text segmentation, text representation and text fragment retrieval. Then, an intelligent evaluation system of English composition is established, and the scoring standard of English composition is determined. On this basis, the design of English scoring module is improved, and an anti cheating module for common plagiarism problems in English composition is added. Finally, the English composition intelligent evaluation system is tested. It can effectively complete the target task, evaluate and correct the composition, and has a higher recognition success rate and accuracy rate. By studying the algorithm and applying it to the construction of English composition intelligent evaluation system, this paper successfully designs a kind of English composition intelligent evaluation system, which promotes the development of teaching work.