Kenichi: The Mightiest Disciple A great entry point if you're new to martial arts anime. Follows a 'weak' kid joining a dojo filled with quirky masters of different styles.

Dragon Ball Series Globally loved for a reason. While Dragon Ball Z escalates to planet-shaking levels, it remains grounded in martial arts at its core.

Naruto Ninjas! While fantastical powers grow central, the series starts with ninja techniques and hand-to-hand, making it a good fit.

Samurai Champloo Unique hip-hop infused take on Edo-period Japan. Amazing sword-fighting choreography and fantastic soundtrack.

Ranma 1/2 Classic zany anime with slapstick comedy. Cursed to transform into a girl when splashed with cold water, Ranma fights rivals across various martial arts.

Megalo Box near-future boxing where boxers utilize mechanical exoskeletons for enhanced power. Unique art style.

The God of High School Over-the-top tournament fighting featuring "borrowed power" from mythological figures. Action and animation are explosive.

Air Master High-flying street gymnast turned street fighter. Focuses on unique fighting styles inspired by gymnastics and aerial combat.

Yawara! A Fashionable Judo Girl Classic shoujo manga with sports emphasis. Gentle introduction to judo with likable characters and a touch of romance.

Levius Steampunk setting with "metal boxing" – fighters augmented with cybernetic limbs. Compelling characters and a focus on strategy.

Basilisk Two ninja clans are forced into a bloody deathmatch during Feudal Japan. Dark, mature theme but amazing ninja tactics and skills on display.

Tenjou Tenge High school setting with outrageous fight scenes between different martial arts clubs. Lots of fanservice, but well-choreographed action.

Hinomaru Sumo Focuses on Japan's national sport. A short motivated sumo wrestler overcomes his size disadvantage with heart and technique. Let me know if you'd like more recommendations, or want a list focused on a particular style of martial arts!