We investigated the influence of salinity at different levels (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12) and alkalinity (0 mmol/L, 10.00 mmol/L, 15.85 mmol/L, 25.12 mmol/L, 39.81 mmol/L, 63.10 mmol/L) on the sperm motility and fertilization rate of Songpu mirror carp ( in this study. The results showed that: 1) The drastic movement time, rapid movement time and life span of the sperm of gibel carp and were the longest when the salinity was 4, and the duration of gibel carp sperm were (90.11±9.03) s, (126.34±13.90) s and (154.27±11.36) s, respectively; while the duration of sperm in were (48.91±1.43) s, (62.19±4.28) s and (90.68±4.46) s, respectively. The drastic movement time, rapid movement time and life span of the Songpu mirror carp sperm were the longest at the salinity of 5, and they were (72.44±9.42) s, (102.16±8.82) s and (206.99±6.65) s, respectively. 2) When the salinity was higher than 8, the initiation of these sperm of the three species were all inhibited. When the salinity was higher than 10, the sperm of gibel carp and were dead, and when the salinity was greater than 11, the sperm of Songpu mirror carp was dead. 3) For alkalinity, at alkalinity of 15.83 mmol/L, the drastic movement time, rapid movement time and life span of the three fishes were the longest, and the sperm motility were significantly greater than other alkalinity groups (4) The fertilization rate of gibel carp and were the highest at salinity of 1, and they were 63.0% and 68.0%, respectively. The fertilization rate of Songpu mirror carp was 72.3% at salinity of 3, which was the highest among all salinities. At alkalinity of 10.00 mmol/L, the fertilization rate of the three fishes reached the highest, which were 75.4%, 54.0% and 66.0%, respectively. Consequently, the effects of salinity and alkalinity on the sperm motility and fertilization rate of the three fishes were obtained in present study, which may provide basic data for the exploitation and development of fisheries in carbonated saline waters in North China.