Lettuce is the most popular salad and cash leafy vegetable with rising demand in urban and peri-urban areas of Ethiopia. However, the crop is neglected in relation to research in soil fertility management and thus its productivity remains very low. Therefore, this experiment was initiated to evaluate the effect of nitrogen and phosphorus rates on growth and yield component of lettuce. The study was conducted in 2025 under irrigation at Zenzelima Campus of Bahir Dar University, Bahir Dar, Ethiopia. The experiment consisted 5*4 factorial combination of five nitrogen levels (0, 46, 92, 138 and 184 kg ha N), and four phosphorus levels (0, 23, 46 and 92 kg ha -1 P 2 O 5 ) using Randomized Complete Block Design with three replications. Data on the growth and yield parameters of lettuce were collected and analyzed using R software. The result indicated that the main effects of nitrogen and phosphorus fertilizer rates were significantly (P < 0.001) influenced plant height, number of leaves per plant, leaf length and leaf width of lettuce. The interaction effects of nitrogen and phosphorus fertilizer rates also significantly (P < 0.001) influenced days to maturity, fresh weight of leaf per plant, marketable fresh leaf yield and total fresh leaf yield of lettuce. Accordingly, increased application of nitrogen (0 – 184 kg ha N) and phosphorus rates (0 – 92 kg ha -1 P 2 O 5 ) enhanced plant height, number of leaves, leaf length and width of lettuce plants in their main effects. Moreover, the highest fresh weight of leaf per plant (330.59 g), highest marketable fresh leaf yield (19.57 t ha -1 ) and total fresh leaf yield (20.90 t ha ) of lettuce plants were recorded in response to the combined application of 184 kg ha -1 N with 92 kg ha . The partial budget analysis revealed that the highest net benefits of 241,070ETB ha -1 with acceptable MRR (190.51%) were obtained in response to application of 138 kg ha -1 N with 92 kg ha -1 which can be recommended for economical production of lettuce under irrigation condition in study area. The experiment is limited to one location and season, repetition of the study in multi-location and season is recommended. -1 -1 P 2 P 2 O 5 O 5 -1 -1