<p>Cassava (<i>Manihot esculenta</i> Crantz) is a staple food for over 800 million people worldwide. However, its production is severely impacted by diseases caused by viruses, fungi, and bacteria. Among these, cassava bacterial blight (CBB), caused by <i>Xanthomonas phaseoli</i> pv. <i>manihotis</i> (Xpm), is particularly damaging. This study aimed to classify the resistance of 11 cassava genotypes, including cultivars, clones, and accessions, using a novel ordinal qualitative scale. Isolate UnB 17 of Xpm, a highly virulent strain from Pará State, Brazil, was cultivated and inoculated into plants by spraying a bacterial suspension of 10⁸ CFU mL⁻¹. Inoculated and mock-inoculated plants were kept in a moist chamber for three days, then transferred to greenhouse conditions for the remainder of the experiment. Evaluations were conducted at 5-day intervals after inoculation. Visual symptomatology was assessed based on a nine-point scale: 0 (no symptoms); 1 (water-soaked angular spots on ≤1/3 of the leaves); 2 (water-soaked angular spots on &gt;1/3 of the leaves); 3 (necrotic spots/scorch symptoms on ≤1/3 of the leaves); 4 (necrotic spots/scorch symptoms on &gt;1/3 of the leaves); 5 (necrotic lesions on the stem or petiole); 6 (necrotic lesions on the stem or petiole with exudation); 7 (wilting with exudation or death of ≤1/3 of the plant); and 8 (wilting with exudation or death of &gt;1/3 of the plant). The data obtained from this rating scale were used to calculate the Area Under the Disease Progress Curve (AUDPC). Hierarchical clustering and the Elbow method identified three resistance groups: moderately resistant, moderately susceptible, and susceptible. No genotype exhibited complete resistance, as all showed typical symptoms of CBB. This study emphasizes the need for repeated trials across different periods and environmental conditions to better understand the resistance and susceptibility of cassava genotypes.</p>