|―Green‖ odors comprise a group of eight structurally related aliphatic alkenals and alkenols which are characteristic for the odor of a wide variety of plant materials. Using an automated olfactometer, the olfactory detection thresholds for ―green‖ odors were determined in six CD-1 mice and compared with that of spider monkeys and human subjects. Detection threshold values for alcoholic ‖green‖ odors (cis-3-hexen-1-ol, trans-3-hexen-1-ol, trans-2-hexen-1-ol and 1-hexanol) ranged from 8.1 x 109 to 8.1 x 1011 molecules/cm3 and for aldehydic ‖green‖ odors (cis-3-hexenal, trans-3-hexenal, trans-2-hexenal and n-hexanal) , from 8.1 x 107 to 8.1 x 1011 molecules/ cm3 . Detection threshold values of ―green‖ odor with double bond ranged from 8.1 x 107 to 8.1 x 1011 molecules/cm3 and for ―green‖ odor without double bond ranged from 8.1 x 108 to 8.1 x 1011 molecules/cm3. Detection threshold value of cis- configured ―green‖ odors ranged from 8.1 x 108 to 8.1 x 1011 molecules/ cm3 and for trans- configured ―green‖ odors threshold value ranged from 8.1 x 107 to 8.1 x 1011 molecules/ cm3. Trans-2-hexenal with a double bond at C-2 position in its molecular structure yielded the lowest detection threshold value when compared the other ―green‖ odors (8.1 x 107 to 8.1 x 109 molecules /cm3) which shows not only the presence of double bond plays a major role in detection but the position of the double bond present. A comparison between the present data and data from the other species showed that CD-1 mice displayed lower detection thresholds for all ‖green‖ odors than human subjects and spider monkeys except for the cis-3-hexen-1-ol odor. These findings suggest that the differences in the threshold values between ―green‖ odors are due to the difference in the molecular structure like the presence of double bond and the position of double bond.