Due to increased bacterial resistance to common antibiotics, tendency towards using herbal extracts is increasing. In this study, antibacterial effects of the extracts of Heracleum persicum, Foeniculum vulgare, Plantago psyllium, Camellia Sinensis, Urtica dioica and Allium sativum on Yersinia ruckeri were investigated in vitro condition. The disc diffusion method, minimum bacteriocidal concentration (MBC) and determination of minimum inhibitory concentration (MIC) of the extracts against Y. ruckeri were employed to determination of antibacterial effects of extracts and furasolidon were used as standard. The MIC of extract of Heracleum persicum, F. vulgare, P. psyllium, C. Sinensis, U. dioica and A. sativum were 400, 75, 250, 250, 75 and 150 (μg/ml), respectively, MBC of these extracts was 610, 100, 500, 250, 150 and 250 (μg/ml) respectively, and diameter of zone of inhibition were 17.6±0.6 (mm), 23.6± 1.2, 20.4 ± 0.9, 18.8 ± 0.7, 21.2 ± 1.3 and 22.6 ± 1.1 (mm) were, respectively, against Y. ruckeri. Results of present study demonstrated that the extracts of F. vulgare, U. dioica and A. sativum were appropriate antibacterial agents against Y. ruckeri. Based on the result of this study, using these herbal extracts were suitable alternative than common antibiotics to treatment systematic infections caused by Y. ruckeri.