Because of its clarity and its simplified way of writing, controlled language (CL) is being paid increasing attention by NLP (natural language processing) researchers, such as in machine translation. The users of controlled languages are of two types, firstly the authors of documents written in the controlled language and secondly the end-user readers of the documents. As a subset of natural language, controlled language restricts vocabulary, grammar, and style for the purpose of reducing or eliminating both ambiguity and complexity. The use of controlled language can help decrease the complexity of natural language to a certain degree and thus improve the translation quality, especially for the partial or total automatic translation of non-general purpose texts, such as technical documents, manuals, instructions and medical reports. Our focus is on the machine translation of medical protocols applied in the field of zoonosis. In this article we will briefly introduce why controlled language is preferred in our research work, what kind of benefits it will bring to our work and how we could make use of this existing technique to facilitate our translation tool.