Spotted wing drosophila, Drosophila suzukii (Matsumura), native to Asia, has become a significant threat to soft fruit crops globally. To develop a classical biological control program for this pest, the obligate parasitoid Ganaspis kimorum (Buffington) was approved in the United States for field release in 2021 as a biological control agent. However, challenges in mass production and maintenance of parasitoid colonies have been common. Here, we share improved methods and offer insights into mitigating issues that limit parasitoid production. Additionally, we present a modified rearing protocol using 2-l plastic containers to produce an average of 307 G. kimorum per container. This information is crucial for implementing successful classical biological control programs against spotted wing drosophila with this parasitoid.