The invention discloses an integrated 
microfluidic chip for screening 
medicine. The integrated 
microfluidic chip comprises a PDMS (
polydimethylsiloxane) fluid channel layer and a glass layer. The PDMS fluid channel layer and the glass layer are bonded with each other by 
oxygen plasma to form a fluid channel unit which is of an irreversible structure; the fluid channel unit comprises a 
concentration gradient generation structural region, an array 
cell culture region and a buffer structural region. The invention further provides a method for applying the integrated 
microfluidic chip. The integrated microfluidic 
chip and the method have the advantages that 
medicine concentration gradient generation, 
chip cell culture, 
medicine stimulation 
on cells, result generation and detection are integrated on the 
chip, the buffer structural region can be opened and closed, accordingly, the 
concentration gradient generation structural region and the array 
cell culture region can independently work and integrally run, and various functions can be flexibly switched over; cell 
inoculation, stimulated, washing and 
dyeing operation procedures and the like can be simplified by the aid of the method, various experimental correlation parameters can be obtained by means of one-step running, and a novel technical platform and the novel method can be provided for medicine screening and cell-medicine research.