Essay marking is a subjective intellectual exercise in which the score reliability can be influenced by many factors such as the test design, the marker's interpretation of the marking criteria, the procedure, and the method used in the marking process. After conducting a literature review this study investigated the reliability of essay marking in high-stakes Chinese Second Language (CSL) examinations in Victoria, where the school-based assessments and the final external examinations are combined to produce one holistic score for each candidate. The subjects were twelve volunteer CSL markers from twelve different secondary schools in greater Melbourne. The data consisted of 24 marking sheets completed by the markers on two separate occasions. Comparison was made between the first and the second marking. The study found that over 83% of the scores awarded in the first marking were subjective. To improve the reliability of the essay marking in CSL, an alternative marking method called the "three-marker method" was introduced. It was evident that this method of marking improved the standard variation, variance, and reliability coefficient of CSL scoring. The outcome of this research could also be applicable to essay marking in other second languages. (Contains 4 tables.)