Seaweed is a biological resource abundantly available in Indonesia, yet it has been hardly used or consumed. This study aimed to analyze the influence of palm sugar [Arenga pinnata (Wumb) Merr.] concentration on the quality of Eucheuma cottonii Doty seaweed jam using true experimental research design. The concentrations of palm sugar were 0%, 30%, 40%, 50%, 60%, and 70%. The results showed that there was an effect of palm sugar concentration on the quality of Eucheuma cottonii Doty seaweed jam. The best treatment in this study was palm sugar concentration of 70%. In this treatment, water content, total sugar, and total soluble solids of seaweed jam were 33.60%, 64.89%, and 54.15%, respectively. In general, the addition of palm sugar improves seaweed jam quality.