The present invention provides a rubber composition having high impact residence, preferred processability and workability which may be used for the manufacture of one-piece solid golf ball, solid core of multi-layered solid golf ball, solid center of thread-wound golf ball, etc. The rubber composition is characterized by that a rubber component is made from a mixture of:(1) 60 to 95 wt % of a polybutadiene containing at least more than 40% of cis-1,4 bond and having a Mooney viscosity [ML.sub.1+4 (100.degree. C.)] of 50 to 70, obtained by using lanthanum rare earth-based catalyst, nickel-based catalyst or cobalt-based catalyst, or a mixture thereof with another polybutadiene obtained by using a catalyst other than the above mentioned one, and(2) 5 to 40 wt % of a polyisoprene containing at least more than 90% of cis-1,4 bond and a Mooney viscosity of 70 to 90.