Gekko japonicus occurs across the main islands of Japan, ranging from northern Honshu in the north and east to Kyushu in the south and west.

[1] Like other species of gecko, individuals of G. japonicus primarily eat insects.

The species is capable of autotomy, and will separate its tail from its body to escape predators.

While this process avoids bleeding, as blood vessels at the base of the tail close to prevent blood loss, the gecko does lose a supply of fat tissue, which it can use during periods where food is scarce.

[2] In Japanese culture, seeing a gecko on one's home is associated with good luck.