UK public-service broadcaster, the BBC, reports that the 820,000 tickets, which went on sale from 0900 local time, were sold in a matter of hours.
Tickets for a number of high-profile events, including the 110m hurdles final, which is likely to feature reigning Olympic champion Liu Xiang, sold out in just half an hour whilst tickets for diving - another sport in which China excels, also sold out quickly.
Buyers have been restricted to two tickets each.
