Nanotechnology has a wide range of applications in many fields, due to the physical properties of small sizes such as the increase in surface area to volume ratio, in the current study, silicon oxide nanoparticles (SiO2- NPS) were synthesized by sol gel method. the synthesized SiO2 nanoparticles were characterized by using XRD, UV-visible spectrophotometry, FTIR and Zetasizer analytical methods. XRD pattern shows the broad peak at (22˚) corresponds to the typical diffraction of amorphous SiO2- NPS, UV-visible absorption peak was found at 240 nm. FTIR is certain the presence of Si-O-Si and Si-O vibration peaks, and Zetasizer confirmed that the confirmed that the synthesized silicon oxide nanoparticles are in the size range of 40-80 nm. Six concentrations of SiO2- NPS were prepared (5, 20, 40, 60, 80, 100 mg/l). Celery seeds were soaked in these concentrations separately and growth indicators were measured. The concentration of 100 mg/L of SiO2- NPS gave the best results in all growth indicators represented by the lengths and weights of the shoots and roots of celery seedlings. it could be concluded with this study the importance of using silicon oxide nanoparticles to improve growth of agricultural crops

SiO2-Nps, Nanoparticles, germination, seedling growth, Celery