The invention discloses a method for detecting formaldehyde content in a hematodialysis concentrated solution packing material. According to the method for detecting the formaldehyde content in the hematodialysis concentrated solution packing material provided by the invention, the formaldehyde content is subjected to assay determination by adopting head space-gas chromatography. The test proves that the method is high in formaldehyde separation degree, high in sensitivity and high in specificity, the formaldehyde content is rapidly and accurately measured, and the method is suitable for quality control of possibly residual formaldehyde in hematodialysis concentrated solution packing materials such as a high-density polyethylene container and an inner cover. Specifically, the detection method comprises the following steps: (1) cutting a to-be-detected hematodialysis concentrated solution packing material into a certain size, and cleaning and airing; (2) performing water-curing treatment on the aired packing material in a closed container; and (3) performing headspace sampling on the soaking solution in the step (2) in a headspace bottle, and detecting the formaldehyde content by adopting gas chromatography.