The Decision Diffusion Model (DDM) serves as a useful framework for describing two-alternative forced-choice (2AFC) perceptual decisions. It effectively differentiates between judgmental and perceptual biases through its parameters. Although extensively applied in visual and auditory decision-making tasks, the DDM has yet to be validated for olfactory tasks in humans. This study aims to validate the DDM within the context of olfactory decision-making. We utilized an experimental paradigm where participants were tasked with identifying the predominant odor in five distinct two-odor mixtures. Our study design involved manipulating the drift rate by creating two levels of difficulty in the odor mixtures. Each mixture was presented 30 times using an olfactometer. We hypothesize that increased stimulus difficulty will result in a lower drift rate. The results from 20 participants will be presented and discussed.