Background; Effortful swallowing training (EST) is a remedial method for the training of swallowing-related muscles in the oropharyngeal phase. However, clinical evidence of its effectiveness is insufficient. Aims; To investigate the effects of EST on tongue strength and swallowing function in patients with stroke. Methods & Procedures; Stroke patients with dysphagia were randomly assigned to one of two groups: an experimental group (n = 12) and a control group (n = 12). The experimental group underwent EST, while the control group performed saliva swallowing. Training was conducted 5 days per week for 4 weeks. Both groups underwent conventional dysphagia treatment for 30 min/day, 5 days/week for 4 weeks. Outcomes & Results; Tongue strength was assessed using the Iowa Oral Performance Instrument. The Videofluoroscopic Dysphagia Scale (VDS), based on a videofluoroscopic swallowing study, was used to analyze oropharyngeal swallowing function. The experimental group showed greater improvements in anterior and posterior tongue strength compared with the control group (p = 0.046 and 0.042, respectively), and greater improvement in the oral phases of the VDS (p = 0.017). Conclusions & Implications; We recommend EST as a remedial strategy for improving tongue strength and oral swallowing function in patients with stroke.