To elucidate the magnetic ordering process in quasi one-dimensional antiferromagnets, hexagonal ABX3 compounds which have spin frustration among the magnetic chains on the triangular lattice, mu+SR experiments were performed on a typical Ising spin system CsCoCl3. Below T(N2) = 9 K, precession component was observed with the precession frequency extrapolated to 4.2 MHz at 0 K. In the partially disordered phase below T(N1) = 21 K, a relaxation component of muon polarization is superimposed on the precession spectra due to static magnetic dipolar field indicating remarkable spin fluctuations despite of long range ordering. In the paramagnetic phase, only the relaxation component was observed. The results are interpreted in terms of domain wall solitons which propagate along the magnetic chains. The missing signal and its temperature dependence are future problems.