Hello Ms. Sidwa, according to the regulations, which just reads as the following "The China Ministry of Railways stipulates that the weight of hand luggage you carry onto the train is limited to a maximum of 20 kilograms (44 pounds); other baggage can be checked onto the train and the related formalities should be transacted at the railway station before your departure"
You may check your luggage if necessary. For more details of the train in China, you may also find it on this website