  Assuming static and spherically symmetric spacetimes in the ghost-free
bigravity theory, we find a relativistic star solution, which is very close to
that in general relativity. The coupling constants are classified into two
classes: Class [I] and Class [II]. Although the Vainshtein screening mechanism
is found in the weak gravitational field for both classes, we find that there
is no regular solution beyond the critical value of the compactness in Class
[I]. This implies that the maximum mass of a neutron star in Class [I] becomes
much smaller than that in GR. On the other hand, for the solution in Class
[II], the Vainshtein screening mechanism works well even in a relativistic star
and the result in GR is recovered.
