The invention discloses a transmission method and system for operation data of an air conditioner unit. The transmission method includes the steps that a data transmission module and a data detection module obtain initial operation data sent by the air conditioner unit simultaneously; the data transmission module organizes the initial operation data and sends the organized distribution operation data to the data detection module; the data detection module compares the initial operation data with the distribution operation data, and when the distribution operation data are abnormal, an abnormal mark corresponding to the data abnormal position is transmitted to the data transmission module; the data transmission module sends the distribution data carrying the abnormal mark to a data storage module. The data transmission module is used for marking the abnormal mark in the data abnormal position of the distribution operation data and sends the distribution operation data to the data storage module, so that when the distribution operation data are called to be analyzed in the later period, the data abnormal position is avoided according to the abnormal mark, and it is guaranteed that the final analysis result is high in accuracy.