[1] The group consists of nine members: Jinho, Hui, Hongseok, Shinwon, Yeo One, Yan An, Yuto, Kino and Wooseok.

[10] In December 2013, Hui, E'Dawn, Yeo One, and Kino participated in the special stage dance at the KBS Song Festival.

[11] In February 2014, E'Dawn and Kino danced at Jirayu Tangsrisuk's 1st concert "James Ji Monkey King Fan Meeting".

[16][17] In February 2015, Jinho and Hui participated in a vocal project group Seorin-dong Children (서린동 아이들) and released a remake of Lee Won-jin and Ryu Keum-deok's 1994 classic "For All the New Lovers".

[23] By the end of the show, Jinho, Hui, Hongseok, Yeo One, Yuto, Kino, and Wooseok were confirmed as the official members of the group.

It was described as a medium-tempo hip-hop song that combines strong beat with a cheerful guitar riff and an intense brass sound.

[44] Pentagon participated in Cube Entertainment's Christmas season song, with their label mates Hyuna, Jang Hyun-seung, BtoB, Roh Ji-hoon and CLC.

[48] Pentagon sold out a reservation for their special mini live & talk concert at Shinagawa Stellaball in Tokyo to commemorate the release of Japan's first EP on March 24.

[61] On September 6, the group released their fourth Korean EP Demo_01 which includes the lead single "Like This", produced by Hui.

On April 2, Pentagon released their sixth Korean EP Positive which features six tracks including lead single "빛나리 (Shine)".

The song eventually becoming a sleeper hit by word of mouth from listeners due to its unique melody and powerful choreography.

[81] On September 10, Pentagon released their seventh Korean EP Thumbs Up!, which features five tracks including lead single "청개구리 (Naughty Boy)".

The theme for the episode was "Korean Lyric Awards Special", which they performed a rendition of Kim Wan-sun's classic hit "The Pierrot Smiles At Us", a song recorded and released in 1990.

[87] On November 25, the group held a fan meeting "PENTAGon MOVINGon" at Nakano Sun Plaza, Tokyo with an attendance of 2,000 people.

[99] In April, Pentagon appeared again on Immortal Songs 2 as a contestant, performing Kim Yeon-ja's "Nation of Morning" in Japan as part of the show's 400th episode special.

[104] On June 16, Pentagon represented South Korea in the annual Star of Asia in Almaty, Kazakhstan that gathers more than 20,000 people at the Medeu High-Rink.

[106] On July 22, Cube Entertainment announced that Yan An would not be able to participate in Pentagon's 2019 world tour, "Prism", for medical reasons.

[107] They released their ninth extended play Sum(me:r) on July 17, without Yan An for health reasons, with lead single "Humph!"

[108][109][110] On February 12, Pentagon released their first full album, Universe: The Black Hall with the lead single "Dr.

[116][117] Pentagon participated in Mnet's reality television competition Road to Kingdom, which aired from April to June.

[121][122] It was the last time Pentagon would perform together before the eldest member Jinho enlisted for his mandatory military service as an active duty soldier on May 11, 2020.

[132] On September 17, Pentagon posted a teaser titled "I've been keeping an eye on you" showcasing Yan An, officially ending his 440-day hiatus.

[136] On October 12, Pentagon released their tenth extended play, We:th, as an eight-member group without member Jinho, who was completing his mandatory military service.

[137] The lead single, "Daisy", is an alternative rock song with a trendy yet intense sound, produced by Pentagon members Hui and Wooseok, and composer Nathan.

[149] The group cameoed in the web drama Nickname Pine Leaf for the SBS YouTube channel yogurD in March.

[153] Jinho was discharged from military service on November 14, without returning to the unit after his final vacation, according to the Ministry guidelines for preventing the spread of COVID-19.

[164] On September 9, they released the song "Love is Pain", a remake of "不如" by Chinese singer Qin Haiqing, as a part of NSMG's project Perfect Match.

[165] On October 9, 2023, Cube Entertainment announced that Yeo One, Yan An, Yuto, Kino, and Wooseok did not renew their contract with the company, though the group would not be disbanding.

[169] Before the official debut of Pentagon, the ten members were chosen as new models of Econeko & Sausando's Organic Ice Cream Bubble Cleanser in 2016.

In September 2018, Pentagon donated 50 million won (approximately US$44,500) to Gangnam Severance Hospital's Respiration Rehabilitation Center for patients with rare neuromuscular disease.