The purpose of the study was to investigate the impact of Manila palm supplementation on rumen fermentation and eradication of gastrointestinal nematodes in goats. Sixteen native crossbred goats, with an average weight of 20 ± 3.1 kg were utilised in a randomized complete block design experiment. Group 1 (control) received ivermectin at a dose of 3.03 μg/kg body weight (BW). Groups 2, 3 and 4 were treated with Manila palm seeds, peel and whole Manila palm extract at a rate of 5 ml/kg goat weight, respectively. The results revealed that Manila palm supplementation did not have a significant impact on feed conversion ratio, feed intake, digestibility, blood urea nitrogen, haematocrit, ruminal pH, ammonia-nitrogen, temperature, total volatile fatty acids, butyric acid or microbial population (P > 0.05). However, the concentration of acetic acid was reduced by Manila palm supplementation, whereas propionic acid was increased, particularly in the Manila palm whole extract group, compared to the ivermectin-treated goats. Additionally, methane (CH₄) production was decreased in the Manila palm-supplemented group when compared to the ivermectin group. Moreover, the faecal egg count decreased after 7 and 21 days of treating the goats with Manila palm extracts. Therefore, the study concluded that supplementation with Manila palm whole extract at a rate of 5 ml/kg goat weight resulted in an increase in propionic acid, a decrease in methane production and faecal egg count, and did not affect microbial populations.