This study aims to determine the energy use efficiency and greenhouse gas emissions in Kaman walnut production. It provides the comprehensive of the energy use efficiency and greenhouse gas emissions associated with the production of Kaman walnut varieties produced in Türkiye. Energy use efficiency indications and greenhouse gas emission ratios were computed for the 2023–2024 production season. The energy use efficiency, specific energy, energy productivity and net energy were computed 3.39, 5.19, 0.19 and 105,083.78 MJ ha−1, respectively. Energy inputs in walnut production contain 17,803.62 MJ ha−1 (40.09%) chemical fertilizers, 14,175 MJ ha−1 (31.92%) organic fertilizers, 7542.72 MJ ha−1 (16.98%) diesel fuel, 1846.80 MJ ha−1 (4.16%) machinery, 1360.80 MJ ha−1 (3.06%) electricity, 953.85 MJ ha−1 (2.15%) human labour, 546.48 MJ ha−1 (1.23%) chemicals, 115.43 MJ ha−1 (0.26%) transportation and 68.36 MJ ha−1 (0.15%) irrigation water. The direct energy is 9925.73 MJ ha−1 (22.35%), indirect energy is 33,940.85 MJ ha−1 (77.65%), renewable energy is 15,197.21 MJ ha−1 (34.22%) and non-renewable energy is 29,215.85 MJ ha−1 (65.78%). The total greenhouse gas emissions were computed to be 1224.28 kgCO2eq ha−1 and the greenhouse gas emission rate was 0.14 kgCO2eq kg−1. It can be said that Kaman walnut production is profitable in terms of energy use efficiency in 2023–2024 production season.