This study investigated whether dry and water-bath thawing protocols affect rooster sperm head morphology using a landmark-based geometric morphometric approach. Ten frozen semen straws were divided equally between the two protocols, and all straws were thawed at 37°C for 30 s. From each straw, ten morphologically intact spermatozoa were selected, giving a total of 100 sperm heads. Twelve landmarks were digitized on each sperm head. The resulting data were evaluated using generalized Procrustes analysis, Procrustes ANOVA, multivariate regression, principal component analysis, and discriminant function analysis. Significant differences between the thawing groups were found for both centroid size (F=4.43, P=0.0380) and sperm-head shape (F=8.21, P<0.0001). Centroid size, however, was not significantly related to shape variation (P=0.1256). The first three principal components explained 32.09%, 25.32%, and 20.53% of the total shape variation, respectively. Most of this variation was observed in the acrosomal region. The overall cross-validated classification reliability obtained from discriminant function analysis was approximately 70%, suggesting moderate differentiation between the groups. The results show measurable differences in rooster sperm-head geometry between the two thawing protocols. Geometric morphometrics detected subtle protocol-associated variation in post-thaw sperm-head geometry. The biological importance of these differences is still unclear because the study did not include fresh-semen controls, independent biological replicates, or functional and fertility measurements.