Kiswahili is the national and official language of Kenya and is a compulsory subject in the school curriculum at primary and secondary school levels. In the Kenya Certificate of Secondary Education (KCSE) examinations, the Kiswahili language paper constitutes tests on comprehension (passage), summary, grammar and sociolinguistics. The Kenya National Examination Council (KNEC) examination reports show a poor performance in comprehension by secondary school students. Perhaps the poor performance might be attributed to the inappropriate teaching approaches among other factors. The study was therefore designed to develop and explore the instructional potential of a Cooperative Learning (CL) approach in the teaching of Kiswahili Language Comprehension. This study was conducted in secondary schools in Kisii Central Sub-County, Kenya. The study adopted the Solomon Four Non-equivalent Control Group Design. It involved 160 Form Two students that were drawn from four schools. Simple random sampling technique was used to select the schools and classes that participated in the study. Students' Attitude Questionnaire (SAQ) was used to collect data. SAQ was checked for validity and piloted for reliability. The tool yielded reliability coefficient of 0.79. The collected data were analysed using both descriptive and inferential statistics. Descriptive statistics were used to describe and summarize raw data using mean, standard deviation, frequencies and percentages. The t-test, ANOVA and ANCOVA were employed for statistical tests of significance at alpha (α) = 0.05. The findings of the study showed that the Cooperative Learning Approach significantly improved the learners' attitudes towards learning of Kiswahili Language Comprehension. This study may help secondary school Kiswahili teachers as they seek to improve performance in the subject.