Mortality in piglets before weaning is associated with major economic losses for the pig production. Mostsuckling piglets die during the first four days after birth, and mostly this is due to non-infectious factors. Causes orrisk factors can be related to the sow, the piglets and/or the environment. The present article reviews the mostimportant non-infectious factors related to the piglets namely low birth weight, splayleg, shaking piglets, navelbleeding, crushing and congenital malformations. Crushing by the sow is the most important cause. Piglet mortalitycan be reduced by treating or intensifying care taking of piglets with an increased risk, but the best results are obtainedby adopting preventive measures.