We performed the quantitative and qualitative analysis on the main disaccharide units of glycosaminoglycans produced by human dermal fibroblasts in the 3-dimensional culture supplemented with L-ascorbic acid 2-phosphate (Asc 2-p) comparing with the monolayer culture system. The addition of Asc 2-p rendered fibroblasts to the organization of the dermis-like 3-dimensional structure in vitro without any pre-treatments with the plastic dish. Main disaccharide units were analyzed using HPLC after 1-phenyl-3-methyl-5-pyrasolone (PMP) labeling. The addition of Asc 2-p significantly increased the total amount of main disaccharide units and, furthermore, the composition revealed it to be more similar to that of the dermis. This 3-dimensional culture may offer a simple and useful system to investigate the glycosaminoglycan metabolism of human dermal fibroblasts in vitro.