The application of SPME/GC-MS in order to determine the (4-chloro-2-methylphenoxy) acetic acid (MCPA) residues in winter wheat seedlings tissues has been studied. The optimal conditions for the SPME of MCPA adsorption were 20 min. in 50oC and 6 min. in 220oC for desorption. The chlorophenoxy herbicide showed different level of accumulation in seedling tissues of studied winter wheat cultivars. The application of the SPME/GC-MS method for the MCPA residues monitoring and possible differences in its biodegradation in the studied wheat tissues is discussed. Key words: chlorophenoxy herbicide residues, winter wheat, DI-SPME, GC-MS