A reagent tube, comprising: a tubular member (1) open at two ends, an upper cover member (2), a lower cover member (3), sealing members (4), and detachable annular members (5). The tubular member (1) comprises an outer tube (101) and an inner tube (102), the outer tube (101) comprises an upper connection section (1011), a middle support section (1012), and a lower connection section (1013) sequentially connected in communication, and the inner tube (102) is disposed inside the middle support section (1012). The two sealing members (4) are respectively provided at cover openings of the upper cover member (2) and the lower cover member (3) to form a sealed accommodating cavity between the upper cover member (2) and the lower cover member (3). The two detachable annular members (5) are provided respectively at a top portion of the upper connection section (1011) and a bottom portion of the lower connection section (1013). Inner threads (103) are provided on inner walls of the upper connection section (1011) and the lower connection section (1013), and outer threads (201) matching the inner threads (103) are provided on outer walls of a lower end of the upper cover member (2) and an upper end of the lower cover member (3). Connections between the upper cover member (2) and the upper connection section (1011) and between the lower cover member (3) and the lower connection section (1013) are established by means of the threads.Un tube de réactif, comprenant : un élément tubulaire (1) ouvert à deux extrémités, un élément de couvercle supérieur (2), un élément de couvercle inférieur (3), des éléments d'étanchéité (4), et des éléments annulaires détachables (5). L'élément tubulaire (1) comprend un tube externe (101) et un tube interne (102), le tube externe (101) comprend une section de connexion supérieure (1011), une section de support intermédiaire (1012), et une section de connexion inférieure (1013) connectée séquentiellement en communication, et le tube interne (102) e
