Optical coherence tomography (OCT) is currently recognized as the gold standard for identifying retinal structural abnormalities in ophthalmology. However, its availability is often limited to large eye centers and research labs due to its high cost and lack of portability. We present a low-cost, portable spectral-domain OCT system with a total cost of materials under $6,000. Compared to current commercial systems, our design offers 50% size reduction and over 80% cost reduction. Image acquisition interface is incorporated and displayed onto a mounted 7-inch touchscreen. Human retinal imaging is demonstrated, and performance is compared with a commercial OCT system. Based on contrast-to-noise ratio analysis, the low-cost OCT demonstrates comparable imaging capabilities.