The trial was executed during 2022 and 2023 seasons on 30 "Earl sweet" Seedless grapevines, seven-year-old vines grafted onto Paulsen rootstock grown in a private vineyard located at the West of Matay Center, Minia Governorate, Egypt. To investigate the effect of different concentration of seaweed extract (0.05, 0.1 and 0.2%) and number of sprayings (once, twice and thrice) during growth stages on yield and berries quality of "Earl sweet" Seedless grapevines. Results revealed that, with increasing concentration of seaweed and number of spraying the parameters under investigation was increased except total acidity was decreased. The best treatment was when vines treated with 0.2% seaweed extract thrice (at the beginning of growth, after berry setting and one month later) during both seasons. therefore, to promote yield and berry quality of "Earl sweet" grapevines, it is recommended to spray the grapevines three times with 0.2% of seaweed extract.