Valid test items are crucial for ensuring that assessments are trustworthy, fair, and useful for their intended purposes. Differential item functioning (DIF) is essential for ensuring that assessment are fair, valid and reliable for all groups, which is critical for making informed decisions and promoting equity. Hence, this study investigated differential item functioning (DIF) in the 2022 Basic Education Certificate Examination (BECE) Mathematics Multiple choice test in Ondo State., Nigeria. The population for the study comprises all junior secondary school 3 (JSS3) students of Ondo State who sat for the 2022 BECE. A sample of 600 scores of 2022 JSS3 mathematics students who sat for the mathematics multiple choice of BECE were selected using purposive sampling technique. The research design employed was expost facto research. The instrument used for the study was 2022 mathematics multiple choice items questions containing 60 items drawn from the JSS 3 Syllabus of BECE in Ondo State. Two research questions and two hypotheses guided the study. The Raju Area Index (RAI) was used to identify items that exhibit DIF while chi-square goodness fit was used to test the hypotheses at 0.05 level of significance. The findings revealed that 43 items (71.67%) of the BECE of 2022 mathematics multiple choice items test showed DIF while 17 (28.33 %) revealed no DIF and BECE of 2022 test items significantly function differentially based on location of schools t= 6.682, p >0.005). Thirty one items (31) were in favour of urban and 12 items in favour of rural testees. But do not significantly function differentially based on gender (t= - 0.794, p< 0.001) Based on the findings it was recommended that test developers should take appropriate steps to minimize DIF and ensure that test items are fair and unbiased.