The flotation of oxidized coal can be well‐improved by dry-grinding, and the flotation of oxidized coal dryground with collector will also be discussed in this investigation. The grinding time is 0 min, 20 min, 40 min, 60 min and 80 min. The dodecane was used as the collector. The flotation tests were conducted in a 1.5 L XFD flotation cell. The combustible matter recovery of oxidized coal dry-ground directly increases with the grinding time. But the combustible matter recovery of oxidized coal dry-ground with collector increases firstly and then has a little decrease while the grinding time is more than 40 min.