A respirator assembly is composed of a respirator, an air purifier, and a connection tube. The respirator includes a first housing having an inflow unit and an air intake. A first pumping unit is located in the first housing for sucking the air through the inflow unit and exhausting the air through the air outtake. The air purifier includes a second housing having an air intake and an outflow unit. A second pumping unit is located in the second housing for sucking the air through the air intake and exhausting the air through the outflow unit. The outflow unit includes a natural-air outlet and a respirator outlet. The connection tube includes two ends, one of which is connected with the respirator outlet and the other is connected with the inflow unit. Accordingly, the respirator assembly can reduce the frequency of replacing the respiratory screen and enhance the quality of filtering the air.