Background: The purpose of this study was to examine glymphatic system function in patients with transient global amnesia (TGA), as well as to conduct a recurrence analysis. Methods: We enrolled patients with TGA and healthy controls from our hospital retrospectively. The patients and healthy controls were all scanned with the same 3T scanner, which included diffusion tensor imaging (DTI). We investigated the function of the glymphatic system using DTI analysis along the perivascular space (DTI-ALPS). The ALPS index was compared between patients with TGA and healthy controls, as well as between patients who had recurrent TGA events and those who had only a single TGA event. Results: Seventy-two patients with TGA and 53 healthy controls were enrolled. Sixty-five patients with TGA had a single TGA event, while seven patients had recurrent TGA events. The ALPS index did not differ significantly between patients with TGA and healthy controls (1.665 vs. 1.618, p = 0.436). The ALPS index, on the other hand, varied significantly according to recurrence in patients with TGA. The ALPS index was significantly higher in patients with recurrent TGA events compared to those with a single event (1.928 vs. 1.636, p = 0.049). Conclusions: We investigated the glymphatic system function in patients with TGA compared to healthy controls for the first time using the DTI-ALPS method. We discovered that these groups did not differ in terms of glymphatic system function. However, glymphatic system function in patients with TGA may differ according to recurrence. Additional research is required to substantiate these findings.