The coffee plant (Coffea arabica L.) is thought to have begun as an understory tree species in Ethiopia's northeastern high rain forests. Bananas (Musa spp.) are commonly intercropped with coffee to provide shade as well as food and money. However, the effect of this practice on coffee production is little known, hence the present study was initiated with the objective of evaluating the effect of intercropping coffee with banana on the yield and quality of both crops. The experiment was carried out using mature coffee intercropped with banana (var. Butezua) in different ratios in Kalu district, northeastern Ethiopia between the 2018 and 2020 cropping seasons. It was conducted in a randomized complete block design with three replications of four intercropping ratios (4C:1B, 3C:1B, 2C:1B, and 1C:1B) and two sole cropped plots (sole coffee, C; and sole banana, B). Over years, analysis of variance showed that intercropping of coffee and banana highly significantly (p < .01) influenced yield and growth parameters, such as clean coffee (a coffee free of taints and defects) yield, total plant height, number of main stem nodes, main stem internode length, number and percent of bearing primary branches, number of fruiting nodes per branch, canopy diameter, leaf length, leaf width, and leaf area of coffee trees. Similarly, coffee bean length, bean width, bean thickness, height up to the first primary branch, and number of primary branches were significantly (p < .05) affected by the treatments. In general, the results revealed that among the intercropped treatments, the staggered planting pattern (4C:1B) gave the maximum clean coffee yield (1,357.3 kg ha −1 ) and fresh banana fruit yield (20,482 kg ha −1 ) followed by the 3C:1B treatment, which gave (1,346.5 and 21,321 kg ha −1 ) clean coffee and green banana yields, respectively.In addition, higher mean land equivalent ratios (LER) of 1.78 and 1.61 and maximum net benefits of 316,265.50 and 302,484.00 Ethiopian birr (ETB) ha −1 were obtained from 4C:1B and 3C:1B, respectively. Therefore, it can be concluded that farmers in the Kalu area and similar agro-ecologies can use these two ratios when practicing coffee-banana intercropping. Further intercropping studies may be required to validate the present results over locations.