Big Bang's music style can be classified for the most part as hip pop music (as seen with the songs "La, La, La" and "Good Bye Baby"), with a little vibe of R&B (as seen with the songs "We Belong Together" and "A Fool's Only Tear"), dance ("Shake It") and mainstream ("This Love") music. Finally, becoming the greatest hit songs of 2007, (as seen with the songs "Lies", "Last Farewell", "Day By Day") electronica is seemingly becoming the new music trend in Korea. However, the members have branched out into different genres in their solo work, including singing ballads and mainstream pop music. Big Bang even once mentioned in an interview that if they want to, they might do trot someday. Dae Sung's new digital single, Look at Me, GwiSun (날 봐, 귀순) consists of a trot song, which has been somewhat controversial considering Big Bang's primary focus on hip-hop.

Big Bang often contribute to writing lyrics for their own music as well as composing despite only debuting in 2006. The most notable from the group to compose and write is leader G-Dragon, as he has composed and written numerous songs for the group, including "Lies" and "Last Farewell", which would later become the group's gateway to stardom. Aside from G-Dragon, the others members have contributed to writing lyrics as well. On a whole, Big Bang has received praises from critics, fans, and other singers alike for contributions to their own materials.

Big Bang often rely on free style and street dancing (as evidenced in their music video for "Good Bye Baby"). They also do break dancing as well. Like the popular boy band Shinhwa, Big Bang's own unique style of dancing is credited to a member of theirs, Seung-ri. Seung-ri has choreographed some of Big Bang's moves (such as jump rope dance from Last Farewell) and has been noted for this.

While most Korean boy bands at the time depended on the "cute" image concept to attract audience and fans, Big Bang instead adopted the "hip hop" image concept, with some of the members slanting their caps in many promotional photos and even having cornrows (most notably Tae Yang) during the early days of their career. The group continued this image concept for the rest of 2006 and into 2007 until the release of their mini-album Always, which showcased the group in a more preppy-ish punk style, sporting modern day fashion (such as the skinny jeans with the converse as seen within the music video of their song "Lie"). Moving further away from the "thug" look, Tae Yang also cut off his cornrows into a buzz cut. Additionally, Big Bang has been noted for being a fashionable group, inspiring teenagers with street-originated flamboyant style.

Big Bang's unique and urban hip-hop sense of style has quickly become popular in Korea as a result, known as the "Big Bang fashion." Usually, the group prefers brands such as Bape, 10 deep, Louis Vuitton, Vivienne Westwood, Phenomenon, and others and are often seen in customized printed hoodies. The group has been noted as well to have brought back the old school fashion, high-top shoes, such as the Nike and Reebok high-top shoes.

Leader G-Dragon is consider by many to be the most fashionable one of the group,  where he tends to wear triangular scarves (shemagh) around his neck, known as "Big Bang scarves" or "Jung Ryu Won scarves", when the actress of the same name began to sport them as well. Additionally, member T.O.P. is also seen sporting sunglasses, especially those worn by American rapper Kanye West. Big Bang's fashion trend is well known throughout the internet fashion portals, thus making them one of the most sought after artists for endorsement products. The group's unique imagery and fashion has led them to release their own fragrance, entitled "BB Bud's My First Fragrance (나의 첫번째 향기)" in early 2007.