IntroductionReading literacy is not only central to students’ academic success during their school years but also crucial to their personal development in their later life. The development of assessment instruments for reading literacy has been of interest to researchers, educators and educational administrators. The purpose of the present study was to construct and validate a comparable item bank for assessing fourth-grade students’ reading literacy.MethodsOne hundred fifteen reading comprehension items were developed and administered to 2,174 Grade 4 students to construct an item bank. Using the test equating technique and balanced incomplete block design, we divided participants into 10 subgroups, and the 115 items were further assigned into 10 test forms. Item response theory software was used to estimate discrimination, items’ threshold parameters, and students’ ability parameters. The criterion-related validity was also examined in 135 Grade 4 students who completed the reading literacy test and verbal self-description questionnaire.ResultsThe final item bank included 99 reading performance indicators to express high achievement. The correlation between the students’ reading literacy and the verbal self-description questionnaire was significant and demonstrated the item bank’s good criterion-related validity. The item bank developed in this study shows good psychometric characteristics and can be used to assess the reading literacy of fourth graders.