The Lidth's Jay (Garrulus lidthi) is a passerine bird in the family Corvidae, native to Japan. It is slightly larger than its close relative the Eurasian Jay, with a proportionately stouter bill and also a longer tail. It has no discernible crest, with the head feathers a velvety black, the shoulders and back a deep purplish blue and all other parts a rich chestnut purple.
This jay has a very restricted distribution occurring only on the southern Japanese islands of Amami Ōshima and Tokunoshima in pine forest, sub-tropical woodland and cultivated areas especially around villages.
The bird nests in large cavities in trees but otherwise the nest is the same as that of the other two Garrulus species with 3-4 eggs.
The voice is similar to that of the Eurasian Jay.
The species was threatened in the past by hunting for its feathers, which were used for decorating lady's hats. Today it is threatened by introduced Small Indian Mongooses, which were brought to its range to control the venomous Okinawa pit viper. The species is fully protected under Japanese law and is increasing in numbers thanks to control of the mongooses.