The goal of the current investigation is to determine if treating an obese rat model's neurological and histological abnormalities with alcoholic brown algae extract can be beneficial. 36 rats were split into two primary groups: The first main group, consisting of six rats, was fed on a standard/basal diet (BD), while the second group (30 rats) was applied for diet-induced obesity (DIO) for eight weeks and divided into 5 sub-groups as follow: group (2), which was fed on BD just as a positive control (obese rats), and groups (3-6) which were fed on BD and given by oral gavages, via a feeding needle with 50, 100, 150, and 200 mg/kg bw/day ethanol extract of brown algae (Sargassum subrepandum) EEBA, respectively. Feeding normal rats on DIO causes them to weigh more than the normal group, have higher feed intake, and have a higher feed efficiency ratio (FER). During the 8-week trial, the BW, FI, and FER values of the healthy group were reported at 0.91%, 12.98 g/day/rat, and 0.075, respectively, but the obese group had higher rates of 57.14, 24.96, and 22.67%. After administering EEBA at doses of 50, 100, 150, and 200 mg/kg bw to feeding rats for eight weeks, the rats' BWG, FI, and FER significantly decreased (p≤0.05), their serum lipid profile variables improved, their neurological conditions (serotonin and dopamine levels and acetylcholine esterase action) improved, and their obesity-linked histological alterations in the adipose tissues and brain were positively manipulated.