About Our School & Team

Welcome to Moorimgoong's Website!

Moorimgoong (MRG) is a Traditional and Mixed Martial Arts Academy (Dojang) that places great emphasis on retaining the fundamental mindsets of martial arts such as discipline, respect, and integrity. Our academy focuses on two distinct aspects of martial arts: practicality and performance.

We are located in the heart of LA between Miracle Mile, Downtown LA, Koreatown, and Mid-City.

Moorimdo is a Hybrid Martial Arts that stems from Kung Fu (Shaolin Long Fist, Baguazhang, and Tang Lang Quan), Tang Soo Do (Korean Karate), Karate, and Tae Kwon Do. MooriMMA is Moorimgoong's Mixed Martial Arts Program that teaches different striking and submission grappling based Martial Art styles from Moorimdo, Kickboxing, Muay Thai, Brazilian Jiu Jitsu, Judo, Tae Kwon Do, Karate, Kung Fu, and more. MooriMMA is unique for its systematized rank system that allows people of any skill set to train at a pace relative to their individual goals and attributes.

Moorimgoong's Founder, Great Grandmaster Yong Moon, opened his first school in Busan, South Korea in 1968. After many years of success, he decided to come to America. His first school was located in New Orleans, Louisiana where he was a local celebrity by the name of “Master Moon." Eventually, he headed west, moving to LA and started another dojang. We have been here in Los Angeles ever since for 29 years. As a 10th degree black belt in Kung Fu and 9th degree black belt in Taekwondo, he decided to create his own traditional martial arts style: Moorimdo.

2nd Generation Owner / Head Instructor

David S. Moon is a 6th degree black belt in Moorimdo under Great Grandmaster Yong Moon and currently runs all classes and operations at the academy. He has trained in many other styles including Kung Fu, Kickboxing, Brazilian Jiu Jitsu, Muay Thai, and Taekwondo to name a few. He is the founder of Moorimgoong’s Mixed Martial Arts Program: MooriMMA, which teaches MMA with a systematized curriculum and belt system.

Moon is an LA native as he was born and raised in Los Angeles, California. He attended Wilton Place Elementary, John Burroughs Middle School, Math and Science College Preparatory, and the University of California, Los Angeles with a major in Sociology and a minor in Film. In his childhood days, he competed in golf and was one of the top ranked juniors in the world. His wide array of knowledge and skills at a young age has translated into his exceptional teaching skills to people of all ages and levels.


Great Grandmaster Yong Moon was born in Hapcheon, South Korea, and began training at an early age as he was born into a martial arts household. He first began training in Tang Soo Do, a very popular style in his region. After many years of practicing Tang Soo Do, he then learned Classical Kung Fu under Master Kang Gum Bang in Busan, South Korea. Master Kang Gum Bang was one of the three Chinese historic masters who emigrated to South Korea during the Communist Revolution in China.

After many years of training under the famous Master Kang Gum Bang, Great Grandmaster Moon decided to start his own school, teaching a hybrid form of both Korean and Chinese martial arts. This fusion of styles is analogous to Bruce Lee’s Jeet Kune Do, which Bruce based it off of his previous training in Kung Fu and Wing Chun.

Great Grandmaster founded The World Martial Arts Federation in 1968, and started in Busan, South Korea. In 1979, he immigrated to the United States and started a school in New Orleans, Louisiana. He quickly rose to fame as “Master Moon” in Louisiana, receiving a plethora of media attention through his martial arts. In 1992, Great Grandmaster Moon moved to Los Angeles, California, started a school, and has been in Los Angeles ever since.

Grandmaster Ari Moon (Co-founder)

Grandmaster Ari Moon is a 9th Degree Black Belt under Great Grand Master Yong Moon in Moorimdo. She has a 9th Degree Black Belt in Taekwondo, Hapkido, and Keomdo. She is the founder of Moorimdew, Moorimgoong's Wellness Program. She has helped build Moorimgoong for the last 30 years alongside her late husband, GGM Yong.

Ari's education includes a Ph.D in Psychology from IMA University, a Business Certification from Yonsei University, and an Early Childhood Certification from Patten University. She has received the highest achievement as a female martial artist from Korea's Guinness World Record.

Chief Master Daniel H. Lee

Daniel H. Lee started his Moorimdo training at 4 years old and is a 6th degree black belt under Great Grandmaster Yong Moon. He has also trained and competed in various other martial art styles up to the collegiate level. He attended the University of California, Berkeley and graduated with a bachelor’s degree in Molecular Biology.

Daniel is currently the Chief Revenue Officer at Hans Biomed USA, a biotechnology company that specializes in biologic, medical devices, and professional cosmeceutical products. He also owns a boutique consulting firm which specializes in helping businesses optimize their operations and grow their overall revenue.

Assistant Master Justin De La Cruz

Justin De La Cruz started training in Moorimdo at the age of 13, and currently holds a Third Degree Black Belt under Chief Master David S. Moon. He is a brown belt in the MooriMMA Program. He began his martial arts training in Shito-Ryu Karate at the age of six and competed in his school days. Justin currently teaches the kids and teens classes at the academy.

Justin was born and raised in Los Angeles, California. He attended Star Christian School and Child Care Center, St Agnes Catholic School, Los Angeles Senior High School, and studied at California State University, Los Angeles, where he earned a bachelor's degree in communication as a first-generation graduate. When he isn't doing martial arts, he likes to hike, swim, and participate in guitar performances for foundations and concerts.