The invention discloses a water pump convenient to assemble and good in stability. The water pump comprises a mounting plate, a machine body is mounted on the upper end of the mounting plate, two connecting pipes are mounted on one side of the machine body, a sleeve ring is fixed to one ends of the connecting pipes, the connecting pipes are slidingly sleeved with sliding sleeves, two sleeves are mounted on the sleeve ring in a penetrating manner, and ejector rods are sleeved with the sleeves. The water pump can be rapidly and conveniently connected with an external water pipe with a flange disc, the connection method is simple, through the multiple manners, connection firmness is ensured, connection seal is improved, the leakage condition is avoided, the application range can be effectively improved, the water pump can be conveniently connected with external water pipes of multiple specifications, meanwhile, during operation, whole stability can be well ensured, when the water pump isnot used, the protection capacity is improved, connecting parts are prevented from being damaged, the influence of vibration or collision on the machine body can be avoided, the service life is prolonged, and work quality during use can be ensured.