At the beginning of 2020, citizens all around the world were streaked by the Corona Virus (Covid-19) pandemic which caused terror far and near. Millions of people were infected and thousands more died ever since the World Health Organization or WHO has declared the Corona Virus (Covid-19) as a global pandemic. Following up on this, the Indonesian government also stated that the Corona Virus problem had become a non-natural national disaster. The President of the Republic of Indonesia and the Regional Government along with their staffs worked  hand in hand to take several tactical steps as an effort to prevent the spread of the Corona Virus (Covid-19) in the community. In this study, authors use one method to make predictions or forecasting, that is the Cheng Fuzzy Time Series method, to predict the number of Covid-19 cases in Indonesia so that the government can take tactical steps after knowing the predicted number of the case. The actual data used is the number of Covid-19 case from July 2020 up until October 2020. From the results of calculations that have been carried out using this method, the conclusion is that the performance is splendid, in the range of MAPE <10, whose error value is 5%. With 95% value of accuracy.