Genetic relationships were studied among eight species of three taxa in the genus Chaenomeles by nuclear ribosomal internal transcribed spacer (ITS) analysis. A genetic distance matrix based on ITS sequences was estimated according to the formula of Kimura-2 parameter and a neighbour-joining phenogram, which were obtained with Clustalx4.1 software. The results showed that the germplasms of Mugua originate from Ch. speciosa (Sweet) Nakai, not including Ch. sinensis (Thouin) Kochne and Ch. cathayensis (Hemsl.) Schneid. The results also showed that 'Yao Mugua' and 'Ornamental Mugua' are the most distantly related species in germplasms.