Strong seedlings are essential for high yield.  To explore the foundation of strong seedlings, we investigated various factors influencing the conversion and distribution of seed storage reserves during seedling establishment in maize inbred lines.  Three maize inbred lines were used to explore the effects of seed size, seed vigor, illumination duration, temperature, water content, and salt concentration of the seedling medium on the utilization of seed storage reserves during seedling establishment.  The results showed that the conversion rate of small seeds was 3.69 to 17.71% higher than that of large seeds.  Moreover, prolonged illumination time was conducive to the formation of strong seedlings.  However, low temperature, drought stress and salt stress reduced the conversion rate of seed storage reserves and increased the root/shoot ratio.  These results could be used to guide field management during seedling emergence and develop improved germplasm with a high conversion rate of seed storage reserves.