Despite of great strides already made,China is still lagging behind Western countries in terms of scientific innovation,which is not parallel with China’s economic achievement. Here I would like to summarize my experience in 30-year science research from the following two aspects:one is the motivation and source of innovation and the other is the value and implication of innovation. I will mainly focus on the relation of innovation with accidental discovery,reversed thought,long term accumulation,and challenge of the authorities. I will also discuss the great role of innovation in developing new theories,guiding medical practice,and dealing with emergencies.