The comments by Mr Zhang, chairman of the China Iron and Steel Association and of Ansteel, one of the country's biggest steelmakers, are among the harshest criticisms of the proposed deal.
The prospect of a merger between two of the world's biggest three suppliers of iron ore has been resisted by many steel companies. This is because of the extra power a BHP/Rio union would have for forcing through price increases for ingredient in steel making.
Last week the Australian anti-trust regulator approved the merger of the two Anglo-American rivals, leaving the European Union's competition authority as the final regulator to decide on the deal. It has until January to do so.