Abstract: The existence of positive almost periodic solutions is discussed for a kind of impulsive Plankton Allelopathy model with delays and harvesting terms. Based on continuous theorem of coincidence degree theory and some analysis technique, the priori bounds of solutions of this system is analyzed in detail, in which there are four possible cases. Some sufficient conditions for the existence of four positive almost periodic solutions of the system are obtained, which complements and perfects the existing relevant results.