nikāya-sabhāga is the product of Sarvāstivāda’s specific subdivision process of all Dharma, and is defined as "the homogeneity of sentient beings. Sarvāstivāda believes that sentient beings become that kind of sentient beings due to the role of nikāya-sabhāga in the process of reincarnation or Path of Cultivation. Therefore, this article examines the role of "nikāya-sabhāga" in Sarvāstivāda's doctrine, especially how to play the role of nikāya-sabhāga in the process of sentient reincarnation or monasticism. Sarvāstivāda advocates that "citta-viprayukta-saṃskāras" is real entity, and the question of whether nikāya-sabhāga is real entity is taken seriously in Abhidharmakośabhāṣya. Regarding Sarvāstivāda's claim, Vasubandhu quoted Sautrāntika and put forward five criticisms. And Saṅghabhadra argued in Nyāyānusāra from Sarvāstivāda standpoint. According to Vasubandhu, the critical point of criticism is that Sarvāstivāda establishes the argument of " notion (buddhi) or provisional designation (prajñapti)of nonparticular(abhinna)", that is, the homogeneous character with knowledge and the name that can explain the homogeneous character. It is a criticism based on epistemology and language theory. Saṅghabhadra's position on " nikāya-sabhāga real entity " is based on the viewpoint of karma theory, which is to follow the Sarvāstivāda doctrine and emphasize nikāya-sabhāga to play its role in the rebirth of karma. Even though Saṅghabhadra did not respond to the argument about " notion (buddhi) or provisional designation (prajñapti) of nonparticular (abhinna) ", Vasubandhu interprets the term nikāya-sabhāga used in the sūtra, not as referring to a discrete real entity, but rather as referring to "conditioned forces of a certain nature to which the designations 'human,' and so on, are provisionally applied much in the same way as homogeneity is applied to rice, and so on."