AbstrakPT Jawasurya Kencana Indah merupakan perusahaan yang berfokus pada produksi corrugated box dansheet. Persaingan dalam dunia usaha semakin ketat mendorong perusahaan terus mengembangkan danmeningkatkan kualitas hasil produksi. Maksimal waste produksi yang ditetapkan oleh perusahaan yaitusebesar 4,80% tetapi pada bulan Desember 2021 proses produksi menghasilkan waste 7,51% dimana 4.46%berasal dari waste bad sheet yang terjadi pada bagian corrugating. Penelitian menggunakan metode FaultTree Analysis (FTA) untuk mengidentifikasi akar masalah dan Failure Mode and Effect Analysis (FMEA)untuk mengetahui Risk Priority Number melalui fase Define, Measure, Analysis, Improve, Control (DMAIC).Berdasarkan hasil penelitian pada proses corrugating terdapat empat jenis defect yaitu krepek, skor variasi,potongan cengis dan gembos dimana krepek memiliki persentase tertinggi sebesar 64,85%. Kegagalanpotensial yang dapat menjadi akar masalah yaitu viskositas lem terlalu rendah, mesin glue roll membawalem tidak stabil, tension break kurang optimal, pemasangan roll kertas terlalu lama, dan air steam tidak dapatkeluar. Dari analisis FMEA diperoleh mesin glue roll membawa lem tidak stabil akibat glue roll aus memilikinilai RPN tertinggi sebesar 125. Usulan perbaikan yang diberikan yaitu melakukan pengecekan kesesuaianstandar kualitas bahan baku lem, melakukan pengecekan glue roll, silinder break, selang angin serta penyaluruap untuk meminimalkan potensi terjadinya defect.Kata Kunci: corrugated carton sheet; defect; DMAIC; FMEA; FTA Abstract[Title: Knowing the Quality of Corrugated Carton Sheet Production Processes Using FTA and FMEAMethods Through the DMAIC Phase (Case Study: PT Jawasurya Kencana Indah Semarang)]PTJawasurya Kencana Indah is a company that focuses on the production of corrugated box and sheet.Competition in the business world is getting tighter, encouraging companies to continue to develop andimprove the quality of production results. The maximum production waste set by the company is 4.80% butin December 2021 the production process produced 7.51% waste of which 4.46% came from bad sheet wastethat occurred in the corrugating section. The research uses the Fault Tree Analysis (FTA) method to identifythe root of the problem and Failure Mode and Effect Analysis (FMEA) to determine the Risk Priority Numberthrough the Define, Measure, Analysis, Improve, Control (DMAIC) phase. Based on the results of theresearch on the corrugating process, there are four types of defects, namely crepe, variation score, cengispiece and gembos where crepe has the highest percentage of 64.85%. Potential failures that can be the rootof the problem are glue viscosity is too low, glue roll machine carrying glue is not stable, tension break isnot optimal, paper roll installation is too long, and steam water cannot escape. From the FMEA analysis, itis obtained that the glue roll machine carrying unstable glue due to glue roll wear has the highest RPN valueof 125. The proposed improvements are checking the suitability of the glue raw material quality standards,checking the glue roll, cylinder break, wind hose and steam distributor to minimize the potential for defects.Keywords: corrugated carton sheet; defect; DMAIC; FMEA; FTA