Seed dispersal by livestock in lowland rangelands has received attention from researchers in recent decades while there has been little research into the dispersal of alpine meadow plants’ seed after ingestion by yaks and Tibetan sheep. This study assessed the recovery and germination of seeds by feeding known quantities of seeds from 20 alpine meadow species to yaks and Tibetan sheep. Seeds from 18 out of 20 of the plant species fed to Tibetan sheep survived ingestion and defecation. All of the species fed to the yaks survived. The recovery rate of undamaged seed ranged from 0.4 to 58.4% for yaks and 0.0 to 28.1% for Tibetan sheep. In general, total recovery of ingested seeds from yaks (28.1%) was significantly higher than that from the sheep (9.4%). Passage time of seeds through the digestive tract ranged from 12 to 96 h for yaks and from 12 to 84 h for Tibetan sheep. Seed recovery was negatively related to seed length (yak, r = –0.59; Tibetan sheep, r = –0.52) but was not related to seed width, seed thickness and seed mass. Seeds defecated by yaks and Tibetan sheep were found to have a range of germination rates which were both higher and lower compared with undigested seed depending on the plant species. It is argued that ingestion of seed by grazing yak or Tibetan sheep may have important effects on the population dynamics of alpine plant species of the Qinghai-Tibetan Plateau.