Hu sheep lambskin comes from a specific breed of sheep of China. Hu sheep are considered a protected breed by the Chinese government. The hair follicles of these sheep have three types of waves, large, medium, and small. There are only few histological reports of Hu sheep lambskin, and there are no modern molecular or biological studies, so the molecular mechanisms underlying the formation of hair follicles with different patterns are not currently known. The aim of this article was to study the molecular mechanism of the formation of these types of hair follicles in Hu sheep. Histological and microscopic analysis indicated that the number of follicles with small waves was not significantly higher than the number of follicles with large waves (P>0.05). The diameters of primary and secondary small-wave follicles were significantly smaller than those of large-wave follicles (P<0.05; P<0.01). The ratio between the number primary follicles and the number of secondary follicles was significantly higher among small-wave follicles than among large-wave follicles (P<0.05). Differentially expressed genes in the skin tissue were screened using an Agilent gene chip and RT-PCR. Differential expression analysis revealed 3 groups of large waves and small waves; 1067, 2071, and 3879 differentially expressed genes; and 137 genes common to all 3 groups. Differentially expressed genes were classified using gene ontology. They were found to be mainly involved in cell differentiation, proliferation, apoptosis, growth, immune response, and ion transport. RT-PCR results of 4 differentially expressed genes were consistent with gene chip results. Combined with related literature, our results suggest that BMP7, MMP2, SNAI1, SFXN1, CDKNIC, MT3, and POU1F1 may have important effects on the formation of large-wave and small-wave hair follicles. This study may enrich knowledge of hair follicle development, and may identify the genes responsible for the formation of hair follicles with different patterns.