Recent interferometric observations of the young stellar object (YSO) HH 30 have revealed a low-velocity outflow in the ¹²CO J=1-2 molecule line. We present here two models of the low-velocity disc winds with the aim of investigating the origin of this molecular outflow. Following Andlada et al., we treated HH 30 as a binary system. Two cases have been considered: (i) the orbital period P = 53 yr and (ii) P ≤ 1 yr. Calculations showed that in the first case the outflow cone had a spiral-like structure due to summing the velocities of the orbital motion and the disc wind. Such a structure contradicts the observations. In the second case, the outflow cone demonstrates a symmetry relatively to the system axis and agrees well with the observations.