Traumatic brain injury frequently results in significant residual deficits in memory and cognitive functioning. There are currently no approved treatments that promote improvement in memory functioning or recovery after severe head injury. Cranial electrotherapy stimulation (CES) has been studied with reported effectiveness in short-term memory and cognitive function in patients with substance abuse. CES has been used in the course of clinical care of patients with closed head injury, with global improvement noted. A double-blind, sham-controlled trial was conducted to assess the effects of CES on memory in 24 brain-injured patients. The mean age for the study population was 24.77 ± 7.03 years, and the mean number of years since head injury was 4.23 ± 4.46 years. Patients received CES or sham CES treatments for 40 minutes daily for the entire 4-week study period. Individual memory testing was administered in four sessions, including subtests from the Wechsler Memory Scale—Revised, California Verbal Learning Test, and Recurring Figures Test. Study results suggest that CES does not improve memory or immediate and delayed recall, with only repeated trial effects showing statistically significant increases in both groups, suggesting learning on retesting for the population in general. Results of this double-blind, sham-controlled evaluation suggest that CES stimulation in brain-injured patients with persistent memory deficits does not improve memory functioning. Further double-blind controlled studies are needed to determine the efficacy of treatments for persistent memory deficits as a sequela of traumatic brain injury.