A steel sheet for double-rolled tubes has excellent formability, and excellent strength and toughness after forming and heat treatment of a tube because of suppressed coarsening of the ferrite grain size and a method for making the same comprises: hot finish-rolling of a steel material containing C: 0.0005-0.020 wt %, and one or two of Nb: 0.003-0.040 wt %, and Ti: 0.005-0.060 wt % at a final temperature of 1,000-850.degree. C., coiling at 750.degree. C. or less, cold rolling, continuous annealing at 650.degree. C.-850.degree. C. for 20 seconds or less, and second cold-rolling at a rolling reduction rate of 20% or less, so that at least one of Nb and Ti is present in a solid solution state in an amount of 0.005 wt % or more, and the crystal grain size in the ferrite structure is in the range of 5 to 10 .mu.m.