Specific heat of UCu3+xGa2-x (0.1 less-than-or-equal-to x less-than-or
-equal-to 0.8) has been measured in a wide temperature range from 1.3
to 250 K. The experiment clarified the systematic x-dependence of the
Sommerfield coefficient gamma and the antiferromagnetic transition tem
perature T(N). This indicates a competition between Kondo effect and R
KKY interaction even in the uranium system.