There is a growing need for studies on ketogenic diet (KD) therapies. Registered dietitian nutritionists (RDNs) should lead efforts to better understand the nutritional risks and benefits of the KD to inform evidence-based practices. The purpose of this study was to explore participation in research among RDNs practicing in KD therapies for epilepsy and identify barriers to participation. This cross-sectional study collected professional experience, research involvement and output, and perceived barriers to conducting research. This study surveyed 66 RDNs practicing in KD therapies for epilepsy. Research involvement was assessed using the Dietitian Research Involvement Survey score. Research output was reported as type and number of publications. Barriers to research included lack of time, resources, administrative support, training, and/or skill. Data were summarized using descriptive statistics, such as means and SDs, medians and interquartile ranges, counts and percentages, as appropriate. The median Dietitian Research Involvement Survey score was 31 out of 60 (range, 16 to 60). Thirty-two participants (48.5%) reported publishing or presenting data, and only 13.6% published an article on ketogenic diet therapies as a leading author. The main barriers to participating in research were insufficient time (83.3%), insufficient funding (81.8%), and priority of work (70.8%). Research involvement scores were not affected by lack of time and resources; however, scores were lower in RDNs reporting lack of interest, training, and skill in research. Although ketogenic RDNs participated in research, most were not leading projects or publications. To increase research involvement among RDNs, focus should include overcoming structural barriers and facilitating knowledge acquisition for those lower on the research continuum.