|Voice (Japanese)||Naoki Bandou|
|First Appearance||Episode 01|
Masamune Tatewaki (マサムネ･タテワキ) is a character in the anime and manga series Battle Spirits Sword Eyes.
He has white hair coming out of the side of his head, and is either balding, or the rest of his hair is covered under a green hat. He has a long mustache, and large eyebrows. He wears a white shirt, with an orange jacket and pants, and always has a pipe in his mouth.
He cares about Tsurugi, but encourages him to go out and find his real mother.
Masamune is Tsurugi's adoptive grandfather. He and his wife Kiku raised him since he was a baby.
Though presently, he lives quietly working in the rocky country of Pacifice, he used to drive a motorcycle.
- A running gag for Masamune is Tsurugi fall off whether he reply to Masamune's calling.
- He shares a seiyuu with Otherworld King when he was old, in Battle Spirits Shounen Gekiha Dan and the elder from Oasis Village in Battle Spirits Brave.