In recent years, much research has focused on studying the damage caused by microplastics to the ecological environment and human health. Indeed, MPs are often consumed by shellfishes and zooplanktons due to their similarity in size to POM (particular organic matter). Especially in zooplankton, the accumulation of MPs in the body affects the reproductive system and the growth rate of juveniles. Moreover, toxins derived from MPs are continuously accumulated in predators of zooplankton and impact the whole ecosystem across the food chain. In this work, we found that even though MPs were internalized by and adherent around Daphnia magna, there were no significant differences in the survival rate of their adults and offspring. However, the population of ovigerous adults under high MPs exposure for 7 days decreased significantly, suggesting an extension of the days of sexual maturity in D. magna. The removal of MPs after 7 days’ MPs treatment resulted in an increase in D. magna juveniles and neonates which indicated their growth was reduced or inhibited in the MPs environment. Overall, the uptake of MPs led to negative effects on population reproduction and the growth of offspring in D. magna.