The purpose of this study was to investigate the syntactic effect Kisabaot, as L1 has on the learning of Kiswahili, as L2 language among Sabaot speaking students in Mt. Elgon Sub- county, in Bungoma county secondary schools. The study population comprised of form four students. The purposive sampling technique was used to select 10 schools that took part in the research and simple random sampling was used to select 30% of the students per class in each of the 10 selected schools. The study adopted descriptive research design. Data was collected by use of essay writing and interview schedule. Descriptive data analysis was used to analyze the research findings. Analysis was guided by research questions. The study revealed that Sabaot syntax was exhibited in the learners written Kiswahili essays as a result of transfer of syntactic structures from Sabaot to Kiswahili. Learners transferred the Sabaot sentence structure to Kiswahili. The study proposes that teachers of Kiswahili be sensitized on the different L1structure of Sabaot speaking learners and make the students aware of the differences. The study also recommends the use of communicative approach as an instructional method among these learners, by intensive writing exercises in Kiswahili as an alternative to diminish L1 interference.