Trichomonas gallinae is a protozoan parasite commonly found in domestic turkeys, columbids, and passerines. Trichomonosis can cause significant morbidity and mortality in these species and has been associated with contaminated bird feeders and waterers. Previously, we found that T. gallinae persisted up to 1 hr in distilled water with organic material; however, it was recognized that pH may play a role in the persistence of isolates of T. gallinae. To examine the effects of pH, we inoculated 1 × 10⁶ trichomonads into plastic containers in 4 different treatments: 500 ml clean distilled water at pH 5.0 or 7.0, or 500 ml distilled water at pH 5.0 or 7.0 plus 15 g organic matter. Aliquots of 0.5 ml were collected from each container at 0, 0.5, 1, 5, 10, 20, 60 min, or 24 hr and inoculated into a flask with Diamond’s media, incubated at 37°C, and examined daily for 6 d. Maximum persistence of T. gallinae for pH 7 was 60 min, whereas the maximum persistence at pH 5.0 was 20 min. Survival was best in the presence of organic matter, regardless of the pH of water. Further research is needed to determine how organic material and pH influences the persistence of T. gallinae, including effects of dissolved oxygen concentrations and ingestion of bacteria by the trichomonads.