A low-cost, simple, sensitive detection method of lactate dehydrogense ( LDH) was developed on paper-based microwell arrays microfluidic device. The phenazine methyl sulfate/nitrotetrazolium blue chloride ( PMS/NBT) detection system was used for LDH detection and the colorimetric results were recorded by both Gel Documentation System and a common camera. Under the optimized conditions, the colorimetric intensity showed a linear correlation to the activity of LDH in the range of 10 to 150 U/L with a limit of detection (LOD) of 9. 44 U/L (3σ) by Gel Documentation System;and the linear range was 15-150 U/L by camera with a LOD of 12. 36 U/L (3σ). Foremost, it was found that human serum albumin (HSA) had an effect on the colorimetric enhancement in this detection system. This low-cost, portable paper-based analytical platform could be suitable for the application in the point-of-care with high sensitivity and reproducibility.