This research was performed to determine the effects of different sowing times (ST1, ST2, and ST3) and biostimulant (Pi-NFS) doses (0, 100, 250, 500 ml da-1) on seed yield components of Italian ryegrass ryegrass (Lolium multiflorum L.) in the continental condition of Eskişehir, Turkey. The results indicated that the main factors significantly affected the seed yield components except for the effect of sowing time on plant height, however, the interaction effect of these factors was significant only on the number of the reproductive tillers and seed yield. There was no significant difference between the ST1 and ST2 in terms of the number of the reproductive tillers, thousand seed weight, and seed yield. Likewise, the values of these components did not differ significantly in the doses of 250 and 500 ml da-1. The highest seed yield was derived from the dose of 500 ml da-1 at ST2 and the values obtained from the doses of 250 and 500 ml da-1 at the ST1 were in the high seed yield group. It was concluded that early sowing time and the doses of 250 to 500 ml da-1 biostimulant application resulted in high seed yield in Italian grass. On the other hand, the dose of 500 ml was more effective in case of delayed sowing time like ST2.