  Separability is one of the most basic and important topological properties.
In this paper, the separability in (strongly) topological gyrogroups is
studied. It is proved that every first-countable left {\omega}-narrow strongly
topological gyrogroup is separable. Furthermore, it is shown that if a
feathered strongly topological gyrogroup G is isomorphic to a subgyrogroup of a
separable strongly topological gyrogroup, then G is separable. Therefore, if a
metrizable strongly topological gyrogroup G is isomorphic to a subgyrogroup of
a separable strongly topological gyrogroup, then G is separable, and if a
locally compact strongly topological gyrogroup G is isomorphic to a
subgyrogroup of a separable strongly topological gyrogroup, then G is
separable.
