Recent innovation diffusion in organisations literature suggests that innovation diffusion dimensions and characteristics are not independent of each other, rather organisational internal environment interacts with both an organisational external environment and an innovation’s characteristics. The purpose of this paper is to examine the validity of the framework consisting of organisational innovation dimensions and characteristics within Saudi Arabian organisations. We test this model with survey data from a large-scale survey of 223 Saudi public and private project-based organisations, these organisations had either adopted, or intended to adopt, the project management office (PMO). To obtain a broad representation of respondents, and to minimise bias, the survey did not target any specific industry. Statistical analysis, specifically exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted to ascertain the factors underlying each construct. Structural equations modelling (SEM) was sequentially utilised to determine the factor structure of the model and to assess the relationships between model constructs. This paper took an initiative step towards a conceptual framework for organisational innovation diffusion, represented by the PMO. Its results revealed that perceived organisational innovation climate functions as a gateway to the organisational innovation diffusion. It was also found that technology mediate the relationships between socio-culture and organisation climate for innovation. More importantly, PMO complexity was not related to the intention to implement the PMO. The quantitative study showed that the framework is a useful tool for studying the diffusion of organisation innovation. The model can potentially form the foundations of a framework for organisations seeking to enhance the organisational innovation diffusion that could in turn strengthen their business performance.