In order to make a comparative analysis of city center retail environments (CCREs) among mega cities in East Asia from the viewpoint of consumer shop-around behavior we have carried out a series of surveys of consumer shop-around behavior at CCREs of Shanghai, Beijing, Taipei, Seoul, Ho Chi Minh and Hanoi. One purpose of the analyses is to estimate the number of people that come into CCREs per day. There has been no theoretical method to estimate total in-migrants to CCRE solely from on-site information, but Saito, Nakashima and Kakoi (2001) first established a consistent method to estimate the probability density over shop-around routes using data from an on-site survey of consumer shop-around behaviors. Using this consistent estimation method, we estimated the actual numbers of consumer shop-around movements within the CCRE of Hanoi based on an on-site survey conducted there. The numbers of pedestrians visiting several facilities were counted by different surveys, and then the results were used to determine the numbers of consumer shop-around movements in the CCRE by expanding the Origin-Destination density estimated from the consistent method. In contrast to a simple biased method, the estimated results of this consistent method drastically improve the accuracy of estimation enough to show the applicability and efficacy of this method for use in further studies. JEL Classification: R12, R15, R41