The announcement of the first COVID-19 case in Indonesia by the President of the Republic of Indonesia is one of the company's external events of particular concern to investors. This study aims to determine whether there is a difference in abnormal return and trading volume activity 5 days before and 5 days after the sub-telecommunication shares as a result of the announcement of the President of the Republic of Indonesia regarding the first case of COVID-19 in Indonesia. The results showed that in the shares of the telecommunications sub-sector there were differences in abnormal returns, but there was no difference in trading volume activity before and after the announcement of the first COVID-19 case in Indonesia by the President of the Republic of Indonesia. This means that the announcement of the first COVID-19 case in Indonesia by the President of the Republic of Indonesia contains information that can be absorbed by investors but does not show up significantly in trading volume activity, while abnormal returns are a significant difference.