The study examined the Effect of Audio-Visual Aided Instruction on Junior Secondary Students’ Interest and Achievement in Fraction in Nasarawa State. The study is a quasi-experimental research in which pretest-posttest was used. Purposive sampling technique was employed to select the schools that were used for this research work. It was purposive in the sense that only schools having functional ICT units that were used for the study. The population was made up of 918 JS1 (504 males and 414 females). Two intact classes drawn from two government schools were selected for this research work. One class was used as experimental group while the other as control group. A validated 40 items Fraction Achievement Test (FAT) and 20 items Fraction Interest Scale (FIS) were constructed by the researchers as instruments for the study. Data were collected and analyzed to answer the research questions using mean and standard deviation while the hypotheses were tested at 0.05 level of significance using ANCOVA. It was found that students taught fraction using audio-visual aided instruction achieved higher than their counterparts who were taught using conventional method. Students expressed higher interest in fraction when taught using audio-visual aided instruction. The study therefore recommends that mathematics teachers should be encouraged to adopt the use of audio-visual aided instruction in teaching and learning of fractions in mathematics to improve students’ interest and achievement in the subject.