Enormous research has focused on investigating innovation process in organisations but only a few are devoted to employee innovation process, thus limiting our understanding of how to organise, foster and successfully manage employee innovation process in organisation. Drawing from the literature, this study extends the two-phase model of innovation process comprising creativity and innovation by proposing a three-phase employee innovation process model that integrates innovation adoption. Using stratified sampling technique and structured questionnaires, data were collected from 430 middle managers of four mobile telecommunication companies in Nigeria. Results of the regression and path analyses to test the hypotheses and model fit support a revised three-phase employee innovation process model showing that employee creativity has direct causal effect on employee innovation and employee innovation adoption, and employee innovation has direct causal effect on employee innovation adoption. Dispositional factors have stronger direct causal effect on employee creativity than contextual factors and contextual factors have stronger direct causal effects on employee innovation than dispositional factors. Both dispositional and contextual factors have similar direct causal effects on employee innovation adoption, though dispositional factors have a stronger causal effects. The study has provided new, empirically based insights into the study of innovation process from employee unit of analysis by extending the innovation process with adoption as a phase concluding the innovation process. Implications for theory and practice are discussed.