Bleach Captain in soul society is responsible for protecting the world from Hollows, Here we will discuss which is most powerful.
10/10 Bleach Captain
RETSU UNOHANA

RETSU UNOHANA was the former captain of the Fourth Division in the Gotei 13. She is the best healer in the soul society along with her immense spiritual pressure which makes her more powerful. Her Zanpakutō (Minazuki) can transform into a giant green creature that can fly. Her Bankai is able to release strong acid which can liquify a person powerful as Kenpachi into a skeleton.
9/10 Bleach Captain
TŌSHIRŌ HITSUGAYA

TŌSHIRŌ HITSUGAYA is the youngest captain of the 10th Division in the Gotei 13. Despite his young age, Hitsugaya is an expert Strategist, Tactician, master Swordman and Kido expert. His Zanpakutō (Hyōrinmaru) has the strongest of all ice-element in Soul Society. Its special ability allow him to control water and ice.
8/10 Bleach Captain
GIN ICHIMARU

GIN ICHIMARU was the captain of the 3rd Division of the Gotei 13. He was a Genius and graduated from Shinigami Academy in just one year due to his exceptional abilities. His Zanpakutō (Shinsō) blade glows white and extends at high speed cutting anything in its way. In its Bankai form, his Zanpakutō retains its appearance but cutting force, length, and speed it’s vastly increased.
He later would betray soul society with Aizen and work with the strongest Espada in Hecto Mundo.
7/10 Bleach Captain
KISUKE URAHARA

KISUKE URAHARA is the former captain of the 12th Division. He is the founder and the 1st president of The Shinigami Research and Development Institute. He is extremely skilled at swordsmanship and is a Kido master. What makes him special is that he have Genius Intellect and have proven this on multiple occasions. He learned Bankai in only three days. His Zanpakutō (Benihime) Bankai was a special ability to restructure anything he touches.
6/10 Bleach Captain
SHINJI HIRAKO

SHINJI HIRAKO was a former Visored and now a current captain of the 5th Division. He possesses the power of Hollow and is a soul reaper. He is a Shunpo expert and possesses immense spiritual power. His Zanpakutō (Sakanade) special ability is to create the World Upside Down. Due to which he was able to land a blow on Aizen.
5/10 Bleach Captain
JOSHIRO UKITAKE

JOSHIRO UKITAKE was the captain of the 13th Division in the Gotei 13. Like Shunsui he is also a dual Zanpakutō user. Despite being ill Jushiro manages to hold his own against Shigekuni Yamamoto. He is a Kido master and has immense spiritual energy. His Zanpakutō (Sōgyo no Kotowari) special ability was to absorb his opponent’s attack from the left sword and release it from the right sword.
4/10 Bleach Captain
KENPACHI ZARAKI

KENPACHI ZARAKI is the current Bleach captain of the 11th Division in the Gotei 13. He was born in a lawless Zaraki district. Due to which he was fighting and killing adults from a young age. He masters in hand-to-hand combat. He did not attend the Shino Academy. Despite that, he was made captain because of his sheer power. His Zanpakutō (Nozarashi) Bankai grants him tremendous strength and power to cut down almost anything that stands in his way.
3/10 Bleach Captain
BYAKUYA KUCHIKI

BYAKUYA KUCHIKI is the 28th head of one of the great noble clans in Soul Society the Kuchiki clan. He is also the captain of the 6th Division. Because of his pride, he acts cold towards his comrades but he deeply cares for them. He is known to be the strongest member of the Kuchiki clan in History. He has mastered Flash steps and Kido and is able to spell up to level 81. His Zanpakutō Senbonzakura’s can separate into a thousand tiny blade fragments. These blade fragments are so small to been seen, they reflect sunlight in such a way they are looked like cherry blossom.
2/10 Bleach Captain
SHUNSUI KYŌRAKU

SHUNSUI KYŌRAKU is the Bleach captain of the First Division and Captain-Commander of the Gotei 13. He has a relaxed and cool type of personality and avoids unnecessary fights. Although he is a peace-loving man, he is an exceptional warrior, he is one the dual Zanpakutō user. His Bankai was so destructive that he avoids using it if they were within his range.
1/10 Bleach Captain
Genryūsai Shigekuni Yamamoto

Genryūsai Shigekuni Yamamoto was the Bleach captain of the First Division and Head-Captain of all “The Divisions”, later called the Gotei 13. He is the founder of the Shinigami Academy and has over two millennia of combat experience, Yamamoto is the most powerful swordsman in Soul Society. His Zanpacto Ryūjin Jakka is the eldest and most powerful in soul society. He proved he is strongest when he fought Shunsui Kyōraku and Joshiro Ukitake both at the same time.