ABSTRACT A field experiment was conducted to determine the effect of nitrogen and phosphorus fertilizers and cattle manure on growth and yield of potato (Solanum tubersum) in Gozamin district, East Gojam, Ethiopia. A field experiment was laid out in a randomized complete block design (RCBD) on factorial combination of five different levels of NP fertilizer (0/0, 41/46, 73/69,105/92, and 137/115 kg ha-1) and three levels of cattle manure (0, 5, and 10 ton ha-1) with three replications. Urea and (DAP) were used as fertilizer sources. ‘Belete’ variety was planted a test crop. There were significant (P<0.05) differences in days to 50% flowering and days to maturity of potato due to the main effect of NP fertilizer and cattle manure. Plant height was also highly significant (P<0.01) affected by mineral NP fertilizer and significantly (P<0.05) by cattle manure. Tuber number per hill and marketable tuber per hill were showed highly significant (P<0.01) to mineral NP fertilizer and significant (P<0.05) to the interaction effect of cattle manure and mineral NP fertilizer. There were highly significant (P<0.01) differences between the treatments of NP fertilizer and the interaction of NP and cattle manure for marketable tuber yield and total tuber yield of potato, and significantly (P<0.05) differences between cattle manure treatments for these parameters. The highest marketable tuber yield (37.407t) and total tuber yield (40.457t) were recorded by applying 10 t ha-1 cattle manure and 137/115 kgha-1 NP fertilizer. Increasing the rates of cattle manure and NP fertilizer significantly increased selected major growth and yield components of potato like plant height, total and marketable tuber number and the tuber weight, and significantly delayed days to flowering and days to maturity. Based on partial budget analysis the optimum net benefit of, 116193.5bir ha-1, with an acceptable marginal rate of returns (MRR) of 1424%, was recorded in the treatment that received 5 tha1*105/92 kgha-1 cattle manure and NP mineral fertilizers . From the main factors of net benefit 104322bir ha-1, with an acceptable marginal rate of returns (MRR) of 6042.5%, was recorded by application of 73/69 kgha-1 NP mineral fertilizers.