Konsumsi roti tawar di Indonesia cenderung meningkat setiap tahunnya. Untuk memenuhi kebutuhan tepung terigu yang berasal dari gandum, Indonesia harus impor dari negara penghasil gandum. Umbi ganyong (Canna edulis Ker Gawl.) merupakan salah satu umbi lokal yang berpotensi dimanfaatkan sebagai substitusi tepung terigu. Penelitian ini bertujuan untuk mengetahui pengaruh kadar air tersesuaikan, suhu, dan waktu Heat Moisture Treatment (HMT) terhadap karakteristik tepung ganyong yang meliputi swelling power, kelarutan, dan lightness, kemudian menentukan perlakuan terbaik dan pengaruh rasio tepung terigu dan tepung ganyong termodifikasi HMT terhadap karakteristik fisikokimia dan sensori roti tawar. Tepung ganyong dimodifikasi dengan metode HMT pada kadar air 25, 27, dan 30% dengan suhu 70, 75, dan 80°C selama 6, 8, dan 10 jam. Interaksi kadar air tersesuaikan, suhu, dan waktu HMT memengaruhi nilai swelling power dan kelarutan dari tepung ganyong termodifikasi HMT. Perlakuan kadar air tersesuaikan 27%, suhu 70℃, dan waktu 8 jam dipilih karena menghasilkan nilai swelling power tertinggi (10,60±0,42 g/g). Modifikasi tepung ganyong dengan perlakuan HMT terpilih (27%; 70℃; 8 jam) menyebabkan peningkatan kadar lemak, karbohidrat, pati, dan amilopektin dan menyebabkan penurunan kadar air, abu, protein, dan amilosa. Selanjutnya, roti tawar dibuat dari beberapa perlakuan rasio tepung terigu dan tepung ganyong termodifikasi terpilih (100:0, 95:5, 90:10, 85:15, 80:20, 75:25, dan 70:30). Roti tawar dari rasio 90:10 dipilih sebagai perlakuan terbaik karena memiliki volume (907,50±28,28 cc) dan hardness (119,08±0,42 g) yang lebih baik, serta memiliki nilai hedonik keseluruhan (5,40±0,05) yang tidak berbeda nyata dengan perlakuan kontrol (100:0). Dengan demikian, roti tawar dari rasio 90:10 berpotensi untuk digunakan dalam produksi roti tawar secara komersial. / The consumption of pan bread in Indonesia tends to increase every year. To meet the demand for wheat flour from wheat, Indonesia must import from wheat producing countries. Canna tuber (Canna edulis Ker Gawl.) is one of the local tubers with potential as a substitute for wheat flour. This research aims to determine the effect of Heat Moisture Treatment (HMT) adjusted water content, temperature, and time on the characteristics of canna flour including swelling power, solubility, and lightness, then determine the best treatment and the effect of the varying ratios of wheat flour and HMT-modified canna flour on the physicochemical and sensory characteristics of pan bread. Canna flour was modified using the HMT method at water content of 25, 27, and 30% with temperatures 70, 75, and 80°C for 6, 8, and 10 hours. The interaction of HMT adjusted water content, temperature, and time affected the swelling power and solubility values of HMT-modified canna flour. The treatment of 27% adjusted water content, 70°C for 8 hours was chosen because it produced the highest swelling power value (10.60±0.42 g/g). Modification of canna flour with the selected HMT treatment (27%; 70°C; 8 hours) caused an increase in fat, carbohydrate, starch, and amylopectin levels and caused a decrease in moisture, ash, protein, and amylose levels. Furthermore, pan bread was prepared from several treatments of wheat flour and selected modified canna flour ratios (100:0, 95:5, 90:10, 85:15, 80:20, 75:25, dan 70:30). Pan bread from the 90:10 ratio was chosen as the best treatment because it had a better volume (907.50±28.28 cc) and hardness (119.08±0.42 g) and had an overall hedonic value (5.40±0.05) which was not significantly different from the control treatment (100:0). Thus, pan bread from the 90:10 ratio has the potential to be used in commercial pan bread production.