The Setul Group, which contains a thick Lower Ordovician to Early Devonian limestone succession, occurs in northwestern Perlis State and the Langkawi Islands, Peninsular Malaysia. We report a lowermost Devonian conodont fauna characterized by Flajsella stygia and Flajsella streptostygia from a limestone section near the small town of Kaki Bukit, in what was previously considered to be Ordovician limestone. The studied limestone corresponds to the youngest part of the Mempelam Limestone. Nine species of conodonts in six genera are systematically investigated herein, of which three species Dvorakia amsdeni, D. philipi and F. streptostygia are the first reports in the Peninsula Malaysia. The stratigraphic correlations of the rock are also briefly discussed. Report (Contributions of authors) Yui Takahashi write the entire parts of the manuscript Sachiko Agematsu review the identifications of conodonts and the stratigraphical correlation in discussion part. Katsuo Sashida Manage the progress of research and review the manuscript Mat Niza Abdul Rahman check the geology of the Peninsular Malaysia