Aim: There are limited numbers of in vitro organ studies both neostigmine and, sugammadex. Up to date, we can reach no study in the literature comparing advantages and disadvantages of two agents in vitro. The study, we aimed to compare and demonstrate in vitro effects of neostigmine and sugammadex in rat trachea with basal and supramaximal tonus. Material and Method: A total of 24 adult male rats were divided into four groups: Group 1; Basal tonus+sugammadex, Group 2; Supramaximal contraction+sugammadex, Group 3; Basal tonus + neostigmine, Group 4; Supramaximal contraction+neostigmine.After anesthesia, trachea of each rats were removed and suspended in Krebs solution. After the vitality of the tissues was shown with acetylcholine and atropine, sugammadex was applied to group 1 and neostigmine to group 3 all in basal tonus. In other two groups, after supramaximal tonus with acetylcholine, sugammadex was applied to group 2, neostigmine to group 4. The contraction responses of each group were compared. Results: There was no significant change in comparison of the sugammadex groups (p>0.05). On the other hand, neostigmine increased tracheal tonus both in the basal tonus group (mean 25-40% ± 3.54), (p <0.05) and supramaximal tonus group (mean 15% ± 2.8) and were statistically significant (p <0.05). Discussion: In our study, neostigmine increased tracheal tone in both basal and supramaximal contractions. Neostigmine use, which may increase the risk of tracheal contractility, can be risky for surgical procedures. Therefore sugammadex may be preferred as there is no effect on tracheal tissue.