Ambrosia artemisiifolia, native to North America, is a notorious invasive plant worldwide. It has posed a serious threat to the biodiversity, stability of ecosystem, economic development and human health in China. Research on the seeding emergence and growth process of A. artemisiifolia, which are important stages in its life history, is essential for invasive management. However, little attention has been paid to the effects of seed characteristics, sowing depth and density at the emergence and growth stages of A. artemisiifolia. In order to study the influence factors of seed emergence and seedling growth of A. artemisiifolia, we conducted a pot experiment to examine the effects of seed size (L, M, S) and burial depth (2, 4 and 6 cm) or planting density (2, 4 and 8 seeds per pot) on the emergence and seedling growth of A. artemisiifolia. It was found that the effect of burial depth on the emergence of A. artemisiifolia was much stronger than that of planting density and seed size, and we also found that the shallower burial depth promoted the emergence of seeds. Under the three different planting densities, A. artemisiifolia showed a relatively high emergence rate at about 67.9%-100%, which was one of the reasons why A. artemisiifolia could successfully colonize in different habitats. The seedling growth was more affected by burial depth and planting density than seed size, and small seeds were more susceptible to the effects of burial depth and planting density. The seedling height and basal diameter were affected by seed size significantly (P<0.05). In general, the seedling height and basal diameter of larger seeds were higher than those of small seeds. In addition, smaller seeds would distribute more biomass to the roots to promote the growth of seedlings. The seedling height and basal diameter were higher at shallower burial depth, while the total individual biomass, individual aboveground and underground biomass increased with the increase of burial depth. As planting density increased, the intraspecific competition of seedlings for water, nutrition, light and other resources increased, resulting in a significant decrease in the aboveground, underground and total biomass of individual (P<0.05). In this study, we found that A. artemisiifolia was more inclined to invade habitats with shallow burial depth and low density successfully. Therefore, for the purpose of preventing A. artemisiifolia invasion, deep ploughing and replacement control technology, which use competitive native plants to compete with invasive plants, can be conducted to inhibit the growth of A. artemisiifolia in China.