The amplitude of nalpha scattering in the vicinity of the He-5() (3/2
+) resonance is expressed in terms of the scattering length and effect
ive range of the dt system. The total cross section of scattering near
the threshold of the dt channel is compared with experimental data. I
t is shown that the phase shift analysis of elastic nalpha scattering
at these energies is an effective method for choosing the low-energy p
arameters of the dt system.