Background: The highlands of North America are where the potato (Solanum tuberosum L.) first appeared. Potato is the most important vegetable crop. Farm Yard Manure undoubtedly boosts crop output because it contains large amounts of plant-growth-critical nutrients that aren’t always available in appropriate levels in the soil and the investigation is aimed to establish the ideal level of farmyard manure for increasing potato tuber production. Methods: During the 2019-2020 agricultural season, the experiment was conducted in the Offa District W/Dekeya kebele Irrigation site under irrigation and rainfall circumstances for ten months. The experiment was created on the spot using the randomized complete block design. There were three replications and four treatments (0 t/ha-1, 2.5 t/ha-1, 5 t/ha-1 and 7.5 t/ha-1). Result: The data analysis of variance showed that varying FYM nutrient rates had significant effects on potato tuber spread and stem diameter. But the effect of FYM nutrient showed a non-significant difference (P less than 0.05) on plant height, leaf area and number of stems. The longest plant height (45.187 cm), wider leaf area (45.417 cm2) and maximum plant spread (42.317) were recorded by the application of 5 t/ha-1 FYM nutrient-applied plot. Whereas the maximum stem number (3.4333) obtained by control plot and stem diameter (3.667 cm) were obtained by the application of 7.5 t/ha-1 FYM nutrient.