Objective: Our previous work documented notable pre-transplant cognitive deficits in older hematopoietic stem cell transplant (HCT) patients with a variety of hematologic malignancies. This present study aimed to explore the impact of hematologic malignancy type on cognitive functioning in older patients awaiting HCT. Method: Participants were 31 allogeneic HCT candidates, 60 years or older with a diagnosis of either leukemia (n = 26) or lymphoma (n = 5), who were scheduled for routine pre-transplant neuropsychological assessment at a university medical center. The total sample mean age was 66.3 (SD = 3.7) with 13.8 (SD = 4.3) years of education. A comprehensive neuropsychological test battery assessing learning, memory, executive, visuospatial, perception, language, and motoric skills was administered to all participants. Results: As individuals with lymphoma presented with a higher performance on a measure of premorbid intelligence (WRAT reading, t(29) = −2.66, p < 0.05, d = .98), this was co-varied in subsequent between group analysis. Individuals with lymphoma performed significantly better on tests assessing visual memory (BVMT Delay Recall, F(2, 28) = 3.66, p < 0.05, d = 1.38), attention (Digit Span, F(2, 26) = 7.04, p < 0.01, d = 1.38), visual processing speed (Stroop Word Test, F(2, 25) = 10.01, p < 0.01, d = 1.04; Stroop Color Test, F(2, 25) = 3.87, p < 0.05, d = 1.04), and response inhibition (Stroop Color Word Test, F(2, 25) = 6.31, p < 0.01, d = 1.00). Conclusion(s): Patients with leukemia performed slightly worse on cognitive measures tapping visual memory, attention and processing speed. Age of onset, treatment differences, and disease stage, have been identified as potential underlying mechanisms.