We have investigated magnetic properties in perovskite titanates ATiO₃ (A=La, Y) by the NMR. Internal field is confirmed to be -10.3 kOe for ⁸⁹Y in the ferromagnetic state of YTiO3 , and to be 〜0 for ¹³⁹La in the antiferromagnetic (AF) state of LaTiO₃. Nuclear spin lattice relaxation rate (T₁^-1) of 139La decreases below T_N 〜140 K due to the AF ordering in LaTiO₃. On the other hand, T₁^-1 of ⁸⁹Y in YTiO₃ (T_C 〜 25 K) decreases below 〜 60 K where the ferromagnetic alignment of Ti moments induced by external fields seems to develop.