The investigation reported herein was undertaken to determine which medium is more practical for the axenic laboratory culture of trichomonads. The growth of Tritrichomonas mobilensis was monitored in 2 different types of commercially available growth media. Although Roswell Park Memorial Institute (RPMI) 1640 medium is typically used as a mammalian cell culture medium, it was found to support the growth of trichomonads as well as the American Type Culture Collection (ATCC) medium 745 under similar conditions. Environmental variables, such as temperature and pH, known to affect the success of trichomonad cultures were controlled. The mean generation times (MGTs) of T. mobilensis in the log phase of growth were 5.1 and 4.9 hr for RPMI 1640 and ATCC medium 745, respectively. A stationary phase of zero growth was reached more quickly in the ATCC medium 745 cultures, and in both media a phase of rapid attrition followed this period of static growth. In assessing the practicality of the media, total cell amplification, as well as factors such as cost, ease of preparation, and storage capacity, were considered.