A quick-donning head harness assembly (10) used in combination with a respirator face mask assembly (12) of the type including a rigid facepiece (14) and a flexible face seal (16), which head harness assembly and face mask assembly may be quickly donned and adjusted without becoming entangled with the wearer's hair. The head harness assembly includes a cap (24) provided with a lower strap casing (24.2) and an upper strap casing (33). A lower elasticized strap passes through the lower casing, the forward ends of the strap passing through adjusting buckles (46) supported by lower corners of the facepiece. Rings (38) are connected to the upper corners of the facepiece (14) and an upper adjustable strap (48) has right and left temple portions (48.2) passing through the ring, the strap being folded back upon itself, the end portions (48.3) of the strap being provided with a "velcro" pile which may cooperate with a "velcro" pile on the upper strap casing (33) for adjustably positioning the upper corners of the facepiece. In addition, a rigid support (26) extends between the upper corners of the facepiece and the top forward corners of the cap (24).