Deca Joins (stylized in lowercase or as deca joins) is a Taiwanese indie rock band that formed in 2013 in Taipei, Taiwan. The band currently consists of four members: Zheng Jingru (鄭敬儒, soloist name: Samjoo) (vocals, guitar), Yang Shanghua (楊尚樺) (guitar), Xie Junyan (謝俊彥) (bass), and Chen Huanggu (陸浩釗) (drums). Their music has been described by critics as "indie," "grunge," and "lo-fi."

The band's original name was FUBAR, but in 2016, they changed their name to Gray Dwarf Star (灰矮星), and in 2017, they switched to their current name of deca joins.