More than 20 different pharmacogenomic tests are being used in the oncology field. The current descriptive study was conducted with 368 oncology nurses in North Carolina to identify and test key elements of Rogers' Diffusion of Innovation Theory that play a role in the adoption of pharmacogenomic testing. Oncology nurses who participated in this study had limited knowledge of genomics and pharmacogenomic testing. Attitudes toward pharmacogenomic testing were positive overall, and the study revealed that oncology nurses in this study routinely use pharmacogenomic testing information. Variable selection methods revealed that total genomic knowledge was more accurately predicted by prior experience and personality variables, pharmacogenomic knowledge was more accurately predicted by personality variables, and attitude was more accurately predicted by prior experience and perceived need of innovation. Based on these findings, several factors play key roles in the diffusion of pharmacogenomic testing within the oncology nursing field. Therefore, assessment of these variables may benefit the widespread adoption of pharmacogenomic testing. Further research should be conducted with these variables to assess the adoption of the innovation.