A field experiment was conducted at Wondo Genet Agricultural Research Center under irrigated conditions during 2018, to evaluate the performance of tomato yield and yield components under an intercropping system with different basil planting densities and row arrangements. it was arranged in a 2 × 4 factorial arrangement in randomized complete block design with three replications each consisting of ten treatments: two basil row arrangements (one tomato row alternating with one basil row (1T:1B) or with two basil rows (1T:2B)) and four basil population densities (66666, 50000, 33333 and 16666 plants ha -1). Results of the study indicated that intercropping system significantly (p<0.05) affected the yield and yield components of tomato. Inter-cropped tomato with basil had the highest yield (36657.8 kg ha-1) as compared to sole cropped tomato (31004.3kg ha-1) and inter-cropping with basil increased its yield by 15.42%. Therefore, basil with a density of 33,333 plants ha-1and intercropped with tomato with 1T:1B row arrangement could be recommended for the wondo genet and similar agroecology area. However, the effect of tomato-basil intercropping on the incidence and severity of major tomato insects and diseases needs further study.