This article examines a very thorny issue of testing English for Specific Purposes (ESP) through the barcode correction system to evaluate the usefulness of distance education. The system was used for the first time as a type of assessment which focuses on enriching student's minimum vocabulary in a variety of English for specific contexts. Henceforth, the barcode correction system is applied in this study on different types of ESP exercises, and they are corrected as they are taught, explained, and consolidated in distance education. To determine online teaching efficiency, the barcode system is used to correct student's papers in a total correction time based on single time 0.45/paper, calculate the rate of mistakes, and diagnose problems of correct answers, and missing marks. The results indicate that there is a high correlation between mistakes and ESP exercises calculated by the correction of barcode reading.