Abstract: A centrifugal coolant pump, comprising a water inlet coupling flange(1), an impeller (2), a volute casing (3), a bearing (4), a bearing housing (5), a transmission shaft (6), and fasteners (7). The bearing (4) is interference installed in the bearing housing (5). The transmission shaft (6) and the bearing (4) inner race are interference fitted together. The impeller (2) is interference installed on the transmission shaft (6). The water inlet coupling flange (1) and the bearing housing (5) are separately disposed on the two sides of the volute casing (3) and fixedly connected via the fasteners (7). The water inlet coupling (1) is provided with a first water inlet (A11), and the volute casing (3) is provided with a second water inlet (B12). The impeller (2) mates with the volute casing (3) to form an independent high-temperature flow path (9) and a low-temperature flow path (8).