Well this might technically violate the 20 year rule but I'm as one of the younger flaired users I feel I should rebel and smash the system so here goes. That said to also cover my arse I'll give you a run down of how perceptions of the have changed throughout Chinese history, in order to give context for the views of the modern day. Also I'm afraid my answer may sometimes slip into how the Mongols in general, as opposed to Genghis specifically, was viewed as the articles generally focus on that.

Right off the bat Kubilai Khan, who set up the Mongol Yuan Dynasty in China, sets about manipulating perceptions of the Genghis Khan and the Mongols more generally. He made huge efforts to sinify the image of the Mongols. In order to make it easier for the Chinese populace to accept the Mongols Kubilai basically tried to fit Mongol rule into the established patterns and assumptions of Chinese culture. This involved acts such as patronising Chinese culture (although in some ways he did impose a Mongol stamp), and historiographical terms this meant fitting the Mongols into the dynastic pattern of Chinese history. Thus Genghis Khan came to be viewed as the founder of a new dynasty who had received the Mandate of Heaven to rule, and was to be honoured as such. This was the pattern for the entire Yuan period with Genghis Khan as the honoured founder of a dynasty.

Right after the Mongols were expelled from China in the rebellion that set up the Ming Dynasty the new Emperors immediately set scholars to the task of writing a history of the Yuan Dynasty. This compiling of their history, something done at the end f every dynasty by the new one, shows that the Ming basically acknowledged the claims that Genghis/the Yuan Dynasty had indeed received the Mandate of Heaven which had given them the right to rule China. However what the historians fail to acknowledge, or perhaps comprehend, is that under Genghis Khan China was subsumed into a larger entity. Instead they portrayed his conquests as simply expanding China, failing to accept that China became one area in a far larger polity. Furthermore there were still some quite negative comments made about various Mongol extravagances and brutality particularly in relation to The Fallow Fields Period. After the Tumu Incident, when Oirat Mongols captured the Ming emperor, comments take an even more negative tone in reaction to a revival of fears of the dangerous tribes in the north. Indeed some Chinese historains begin to try and complete dismiss the importance of the Mongols/Genghis in Chinese history. One scholar, Chang Huang, called the Mongol period "history outside history" a blip in the usual patterns of Chinese history.

The next dynasty the Qings, likely due to its own steppe roots, took a rather more positive of Genghis/the Mongols. For example they stopped printing some histories written in the Ming period which were too bitterly critical of the Mongols. Furthermore there was a move back to seeing Genghis as an admirable founder of a dynasty who had received the Mandate of Heaven.

Finally we arrive at the modern period with the Chinese Communist Party taking power. Here attitudes are quite complex. On the one hand the fact their intellectuals had a tendency to follow Soviet opinions in a variety of fields, including history, as they saw the USSR as the model to emulate. The USSR historians, in keeping with Russian tradition, tended to have a uniformly negative view of Genghis Khan portraying him as a brutal exploitative feudal conqueror (anachronism be damned). On the other hand we see signs that the Chinese might not be so poorly disposed as the Soviets e.g. the 1942 slogan 'Learn from Chinggis Khan's revolutionary spirit the solidarity of national minorities.' In the 1960s as China split politically from the USSR the emphasis on the positive aspects of Genghis Khan and the Mongol Empire increased. They stressed the stability and wealth of much of the Yuan period as well as the development of trades and crafts. Furthermore some even actively praised Genghis Khan's conquests as being a "progressive" as his conquests allowed other countries to come into contact with Chinese culture and science which they term more "advanced" than that of other areas (all hail cultural chauvinism).