Background: Origanum onites L. is one of the most important export plant collected from natural flora and cultuvated in Turkey. Methods: This study was conducted to determine the effects of different doses of chicken manure on yield characteristics of O. onites, in Odemis, Izmir ecological conditions during 2014 and 2015 vegetation periods. The experiment was established as randomized blocks design with three replications and five chicken manure (0, 10, 20, 30, 40 ton ha(-1)) were applied. Results: Plant height, fresh herb yield, dry herb yield, dry leaf yield, dry stem yield and essential oil content were significantly affected by year, harvest number and chicken manure doses. Mean value of the plant height ranged between 56.80 to 94.87 cm, fresh herb yield was 54000.0-135150.0 kg ha(-1), dry herb yield was 5770.7-31040.7 kg ha(-1), dry leaf yield was 3560.7-15470.7 kg ha(-1) and dry stem yield was 1430.6-19060.0 kg ha(-1). The total essential oil content ranged between 3.5-5.4%. Conclusion: For the highest drog herb and drog leaf yields, which is the most important features for the production of oregano, 20 ton ha(-1) of chicken manure application can be recommended. 30 ton ha(-1) chicken manure dose can be suggested as the effective for the essential content.