Germination and seedling vigor are important factors for the growth and yield of sweet corn. Then PGPR-1 is a biofertilizer containing bacteria that promote seed germination and seedling growth. This research aimed to study the optimum rate of PGPR-1 biofertilizer on germination and seedling growth of sweet corn. The experimental design was CRD (Completely Randomized Design) which consisted of 7 treatments: using biofertilizer PGPR-1 at 2 rates of 25 and 50 g/seed 1 kg, in combination with 1. Immediate planting 2. leave it for 1 day before planting 3. leave it for 2 days before planting and 4.no application of PGPR-1 biofertilizer (control). The results showed that sweet corn seeds inoculated with PGPR-1 bio-fertilizer at the rate of 50g / seed 1 kg in combination with immediate planting tended to be the best treatment, because it increased germination percentage, speed of germination and seedling growth (shoot height and root dry weight). But it was not statistically different from the treatment using bio-fertilizer PGPR-1 at the rate of 25 g/seed 1 kg in combination with leaving it for 2 days before planting and using bio-fertilizer PGPR-1 at the rate of 50 g/seed 1 kg in combination with leaving it for 1 day before planting. While application of PGPR-1 biofertilizer at all rates did not differ statistically when compared with the control on seedling root length.