Biourine is a liquid fertilizer that contains complete elements, namely nitrogen, phosphorus, and potassium in small amounts as well as zinc, iron, manganese, and copper. Biourine can provide an increase in plant yields that is almost the same as plant fertilizers, besides that it can control Fusarium wilt disease. This study aims to determine the effect of Trichoderma biourin application on plant growth, Fusarium wilt disease and onion yield. The research was conducted using an experimental method in Senteluk Village, Batu Layar District, West Lombok Regency, West Nusa Tenggara using a Split Plot Design consisting of 2 factors. As the main plot, the shallot varieties consist of three levels, namely Bali Karet, Ampenan and Keta Monca, while as a sub-plot, the Trichoderma biourin application method consists of four levels, namely: without biourine, spraying the soil surface, spraying seed tubers, and spraying on plants 21 days after planting. The treatment was a combination of shallot varieties and Trichoderma biourine application method, each of which was repeated three times, so there were 36 experimental units. The results showed that: (a) The application of liquid biourine by spraying the soil surface, spraying seed tubers and spraying on plants 21 days after planting could increase the growth and yield of shallot bulbs. (b) The Bali Karet shallots varieties are more resistant to Fusarium wilt disease when compared to Ampenan and Keta Monca varieties.