The present study was conducted to evaluate and compare the efficacy of trisin® (3 day, in water medication) with those of baytril® and tylan soluble® for control of experimentally induced Mycoplasma gallisepticum (MG) infection in 10 day old specific-mycoplasma free chicks. Chicks were inoculated intra-tracheally and into the sinus with MG R-strain. Five groups, each of 50 chick were used and designated as group A (uninfected, untreated), group B (infected, untreated), group C (infected, trisin® treated), group D (infected, baytril® treated) and group E (infected, tylan soluble® treated). Birds in all groups were observed during and after treatment for respiratory signs, mortality and body weight gain. Postmortem examination, assessment of lesions and serology were examined. No adverse reactions to medications were observed. In this trial, treatment by trisin® (1 gm/L) or baytril® (1 mL/10 kg) or tylan soluble® (50 mg/kg body weight or 0.5 gm/liter) markedly reduced mortality to 6%, 10% and 8%, respectively. The clinical signs score of trisin® treated group were markedly lower than those of baytril® or tylan soluble® treated ones. Trisin® markedly reduced lesion scores when compared with baytril® or tylan soluble®. Trisin® markedly improved weight gain when compared with baytril® or tylan soluble®. In conclusion, trisin® is a very effective drug for the control of MG infection in broilers.