Abstract: This paper investigated the application of Multidimensional Three-Parameter Logistic model (M3PL) in assessing and evaluating an English multiple-choice test. Guessing parameter, when put in the picture, has been proved to strengthen the results of test validation. The data was gathered from 488 non-English majors taking an English final test at a university in Ho Chi Minh City, Vietnam. The findings, therefore, suggest how M3PL can be utilized in the test development process.