Lavash bread is a traditional food in West Asia and the Middle East, with its consumption increasing in recent years. This study aimed to assess the impact of adding 5%, 10%, 15%, and 20% quinoa flour on the rheological properties of wheat dough, as well as the sensory and chemical characteristics of lavash bread. As the quinoa flour content increased, sedimentation value and mixing tolerance index decreased, while water absorption, dough development time, and dough softening increased. The addition of quinoa flour reduced the extensograph energy value and extensibility but increased the extensograph ratio of elasticity to extensibility. Lavash bread made with quinoa flour remained light in appearance, though its lightness (L*) decreased, and redness (a*) and yellowness (b*) increased with higher quinoa content. Quinoa also improved the chewiness and flexibility of the lavash bread without affecting its appearance, taste, or odor. Notably, the overall acceptability of the bread increased as the quinoa flour content rose. From a nutritional perspective, protein, lipid, fiber, sugar, and ash contents increased, while starch content decreased with the addition of quinoa. Furthermore, significant increases in the levels of aspartic acid, alanine, arginine, valine, leucine, and lysine were observed. In conclusion, incorporating 20% quinoa flour into lavash bread enhances its nutritional value and functional properties, making it a healthier alternative to traditional wheat lavash.