Macau’s tourism industry has witnessed a significant growth in the past few years. It is very important to forecast the future trend of inbound visitors. This research uses the grey forecasting model to estimate possible number of visitor from Mainland China to Macau by using the official figures on visitor arrivals to Macau published annually by Statistics and Census Service of Macao SAR Government. After formulating the most idea forecast model to estimate the number of inbound tourists, we compare the forecast result with actual annual visitors to Macau to check accuracy and error value. It is intended that the research finding will not just provide the related governmental departments and industry with a foundation to base their decision making on, but also act as reference point for conducting further research by fellow academicians.