[en] Rain water samples, which were confirmed to contain fresh nuclear debris from French nuclear explosions carried out in the southern Pacific Ocean in 1970 and 1971, were subjected to γ-ray spectrometry with a planer type of Ge(Li) detector, and were found to have much higher uranium concentration than usual rain water samples. Uranium isotopic ratios (²³⁵U/²³⁸U) of several rain water samples and soil samples were measured using neutron activation method, and it was found that the uranium isotopic ratios of the rain water samples which contained nuclear debris from the French explosions were 0.0022 -- 0.0029, very low compared to that of natural uranium (0.0073). Thus, it is assumed that the French nuclear explosions produced appreciable world-wide depleted uranium fallout. (auth.)