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The structural and magnetic properties of Dy2AlFe13Mn3 compound have been investigated by means of x-ray diffraction and magnetization measurements. The Dy2AlFe13Mn3 compound has a hexagonal Th2Ni17-type structure.Negative thermal expansion is found in the Dy2AlFe13Mn3 compound at the temperatures ranging from 245 to 344Kby x-ray dilatometry. The coefficient of the average thermal expansion is -α = -1.1 × 10-4K-1. The spontaneous magnetostrictive defcrmations in the 105-360K temperature range have been calculated by means of the differences between the experimental values of the lattice parameters and the corresponding values extrapolated from the paramagnetic range. The result shows that the spontaneous volume magnetostrictive deformation ωs increases from 7.0 × 10-3at 105K to 9.1×10-3 at 245K, and then decreases with the temperature increasing. The spontaneous linear magnetostrictive deformation λc along the c axis decreases as temperature increases. The spontaneous linear magnetostrictive deformation λα in basal-plane increases from 0.8×10-3 at 105K to 3.4×10-3 at 270K, and then decreases with the temperature increasing further.