Abstract: The present disclosure discloses a safety warning system for a child safety seat including a first detection device sending a first detection signal when detecting that the top tether is tensioned, a second detection device sending a second detection signal when detecting that the ISOFIX connector is installed in place, a third detection device sending a third detection signal when detecting that the buckle is buckled, and a transfer control device receiving first, second and third detection signals. When at least one of first, second and third detection signals is not received, the transfer control device sends an alarm signal to remind the user whether the top tether is installed or buckled, ISOFIX connector and buckle are correct, ensuring the safety and comfort of the child, and improving the installation efficiency of child safety seat. The present disclosure also provides a child safety seat.