In this paper, we proposed the user uninterruptibility estimation method based on focused Application-Switching (AS) during PC work for establishing information display timing control scheme with less intelligent activity disturbance for users. At first, we collected and analyzed the PC operation records and the subjective uninterruptibility of users. From the analysis, we selected features in AS timing that affect user uninterruptibility. Then, we provided the estimation method based on co-occurring features that are observed in AS timing, and confirmed the availability of our method.