Single crystals of AlFe2B2 have been grown using the self-flux growth method, and then we measured the structural properties, temperature- and field-dependent magnetization, and temperature-dependent electrical resistivity at ambient as well as high pressure. The Curie temperature of AlFe2B2 is determined to be 274 K. The measured saturation magnetization and the effective moment for the paramagnetic Fe ion indicate the itinerant nature of the magnetism with a Rhode-Wohlfarth ratio MCMsat≈1.14. Temperature-dependent resistivity measurements under hydrostatic pressure show that transition temperature TC is suppressed down to 255 K for p=2.24 GPa pressure with a suppression rate of ∼−8.9 K/GPa. The anisotropy fields and magnetocrystalline anisotropy constants are in reasonable agreement with density functional theory calculations.