We report systematical measurements of specific heat, electrical resistivity and magnetization on heavy-fermion antiferromagnets U 14 Au 51- x Cu x (0≤ x ≤9) and UAu 3 and a paramagnet UAu 2 in wide temperature and magnetic field ranges. The linear-like decrease of T N of U 14 Au 51- x Cu x with x , corresponding to the decrease of the lattice constants, is interpreted as a chemical pressure effect. The high field magnetization process of U 14 Au 51- x Cu x at 4.2 K exhibits a metamagnetic-like jump around 25, 23 and 14 T for x =0, 3 and 9, respectively. The heavy fermion ground states of U 14 Au 51 and UAu 3 have been studied by specific heat measurements down to 0.5 K in magnetic fields upto 8 T.