A legendary Pokémon that was thought to be extinct. It is said to be able to disappear at will and appear before those with pure hearts and a strong desire to meet it. It was discovered and named by Dr. Fuji in the depths of the jungle.

It has a appearance reminiscent of small animals such as weasels, with a long, thin tail that is rounded at the tip. Its body color is pink, and its entire body is covered in fine fur. The alternate color form is entirely light blue.

It is highly intelligent and can learn all moves except for a few using move machines or move tutors. It is said that its genes contain information on all Pokémon, and there is a theory that Mew is the ancestor of all Pokémon.

The following diary entry was left at the Pokémon Mansion in the Kanto region where Dr. Fuji lived, but Mew's egg group is Egg.

 Diary February 6

 Mew gives birth to a child.  

The newly born junior  

is named Mewtwo...

In terms of game development, Mew was originally intended to be a Pokémon that only existed in the setting and did not appear in the game. However, development staff member Shigeki Morimoto secretly added Mew's data to the game's limited free space, and due to a bug in “Red and Green,” its appearance was revealed, leading to it becoming known as the 151st Pokémon.

After its existence became known among players, it was officially distributed several times, but each distribution campaign saw an overwhelming number of applications, making it extremely difficult to obtain the official version. This led to the widespread circulation of bug techniques to create Mew, further fueling the use of bug techniques in 'Red and Green.' Furthermore, it was no exaggeration to say that most of the Mew in circulation were generated by bugs. There were also instances of players being deceived into exchanging their Pokémon for Mew, among other rumors and exchanges related to Mew, illustrating how many players were eager to obtain it.

Currently, through occasional online giveaways, nearly all players have the opportunity to obtain Mew. Since bug techniques no longer exist in large numbers as they did in the past, distinguishing genuine Mew from modified Pokémon is sufficient.