Restoration of mortar is an important part of the restoration of lacquerware relics. In order to disclose the materials of three typical mortars used for lacquerwares collected in the Palace Museum, X-ray fluorescence spectrometry, micro-X-ray diffraction, Fourier transform infrared spectrometry, fiber microscopy and pyrolysis-gas chromatography/mass spectrometry were applied to identify the inorganic and organic components contained in the lacquerware mortars. The research results suggest that 1) mortar of the plum blossom and banana leaf-styled Guqin of the Ming Dynasty is composed of animal horn or bone ashes, Chinese lacquer and a small amount of vegetable oil; 2) mortar of the black lacquer throne with gold decoration of the Qing Dynasty is composed of clay containing calcite, boiled tung oil and porcine blood; in addition, the sample also contains hemp fiber, which should be the linen mounted between the wooden body and the mortar layer of the throne (mortar of the throne not only provides a flat surface for lacquering, but also solidifies the linen); 3) mortar of the black lacquer couplets with filled gold characters written by Zhang Tingyu of the Qing Dynasty is composed of clay, boiled tung oil and porcine blood. The analytical methods applied in the present study permits rapid and accurate identification of the materials of mortars used for lacquerwares, especially the organic binding materials. Material selection of the three typical mortars is consistent with the traditional manufacturing methods for lacquerwares, especially furniture and objects of the Ming and Qing Dynasties. These research results could be directly applied to the restoration of lacquerwares.