Abstract: The nonlinear plasma density waves in a low-β cylindrical symmetry magnetic tube are discussed. The results show that: (1) if |(a/M²-1)E₀| < 1 or a/M²> l, |(a/M²-1)E₀| > 1 and G_m > 1 + |(a/M²-1)E₀|, there exist periodic waves; (where a = Ti/Te+ 1, Ti and 7% are the ion and electron thermal energies respectively, Mis the ratio of phase velocity of wave and ion acoustic velocity, E₀ isinitial electrical field, (G_m=√a/M²exp(1-a/M²)/(2a/M²)). (2) if |(a/M²-1)E₀| = 1 and G_m≤2, there exist shock waves; (3) if a/M² > 1, | (a/M²-1)E₀| = 1 and G_m>2, there exist hollow solitons; (4) if a/M²< 1, |(a/M²-1)E₀|≥1 and G_m> 1 + |(a/M²-1)E₀| or |(a/M²-1)E₀| > 1 and G_m≤ 1+|(a/M²-l)E₀|, there exist raised solitons. The amplitude of waves is discussed also.