Applying different forms of a single test on different times may cause at least different difficulty level problems. To compare the scores which are provided from different forms need to be equated. The scope of this research study was to equate 2008 spring and fall ALES quantitative-1 scores with using linear and equipercentile equating methods and to suggest most appropriate method. The findings showed that there was a linear relation between raw scores and equated scores. A result of linear equating difficulty of tests were varying along the score scale; a result of equipercentile equating fall test was more difficult than spring test at the low scores and easier than spring at the top scores. At the end of the study, it is seen that the most appropriate method for equating test scores was equipercentile equating.