External and internal parasites are the major cause of many problems in dairy cattle. This study estimated the association of   external parasites infestation and blood parasites infection with milk production and it`s components.  Identification and prevalence of ticks, Babesia and Theileria species were carried out on 300 local moderate lactating Friesian cattle .The effect on chemical components of milk and other milk parameters including   amount and immune suppression were studied. 75% of dairy cattle   were infested with ticks while 9% were infected with Babesia spp. and 10% were infected with Theileria spp. , levels of both calcium and zinc in serum of dairy  cattle infested with ticks , infected  with Babesia spp. and infected  with Theileria  spp. were  markedly decreased (9.3±0.5, 8.7±0.6 & 9.2±0.7 mg/dl ) respectively for calcium and (0.37±0.001, 0.23±0.001 &0.31±.001 µg/dl ) respectively for zinc .  Ig E levels were increased in dairy cattle infested with ticks (1.7±0.03 µ/ml), infected with Babesia spp. (1.1±0.02 µ/ml) and infected with Theileria spp.  (1.2±0.02 µ/ml) than clinically healthy ones (0.95±0.02 µ/ml). Significantly decreased  Calcium levels in milk of dairy   cattle infested   with ticks , infected  with Babesia spp. and infected with  Theileria  spp. (144.5±13.8, 129±12.3 & 132±11.4mg/dl) respectively than that of  clinically healthy ones (159.4±12.7mg/dl). Also zinc levels in milk recorded decreasing  values in  dairy cattle infested   with Ticks, infected  with Babesia spp. and infected  with Theileria  spp. (8.5±0.07, 6.9±0.8 & 7.2±0.6 µ mol/dl) respectively than that of  clinically healthy ones(12.7±0.09 µ mol/dl).