The defender posted the messages ahead of the Blues' 3-0 win over Arsenal at the Bird's Nest in Beijing on Saturday and the 21-year-old was jeered during the pre-season friendly.
He has since apologised for his comments and deleted the posts and said it was "not intentional" to cause any offence.
And on Sunday afternoon, the Premier League champions published a statement on their official website also apologising.
"On July 22, Chelsea Football Club experienced the warmth and friendliness of Chinese fans at the National Stadium. However, we were surprised and disappointed that one day prior to the match, one of our young players, Kenedy, posted messages on his social media account that caused great offence and hurt the feelings of the people of China.
"Unfortunately, even though he quickly deleted the messages and apologised, and the club also apologised via our Chinese social media channels, the damage had already been done. Chelsea Football Club once again solemnly and sincerely apologises.
"Kenedy's actions were a mistake that he will learn greatly from. His behaviour does not represent the entire team and does not align with the club's high expectations and strict requirements of its young players. He has been strongly reprimanded and disciplined.
"Everyone at Chelsea Football Club has the utmost respect and admiration for China and loves our Chinese fans. It is because of this that the negative impact we have seen over the last two days has left us shocked and saddened. Once again, we sincerely apologise for the hurt caused to our Chinese fans as well as to the Chinese people.
"The match was a great cultural exchange event between China and Britain and the club is extremely grateful to China for its hospitality, which has brought us closer together in friendship. We very much hope to build on our strong relationship with our Chinese fans and friends, joining hands firmly with China in future for further co-operation
"We offer this apology with utmost sincerity. We have listened carefully to the criticism and will use the lessons learnt over the last two days to improve our processes in future."
Kenedy, who Chelsea signed from Brazilian club Fluminense in 2015, made three appearances last season.