A survey was made from March 1978 through Feb. 1979 to know infection rate of parasites and incidence of diseases in 1968 cattle of 240 rearing and fattening cattle herds (1746 Korean native cattle, 186 Holstein, 34 Charolais and 2 Hereford) raising in 28 cities and counties of Gyeongbug district. The results obtained are summarized as follows: 1. The rate of nematoda infection was about 49.0% in the examined cattle. These nematodes were identified as Mecistocirrus sp., Oesophagostomum sp., Bunostomum sp., Trichostrongylus spp., Strongyloides sp. and other 3 species. Infection rate of nematoda in fattening and breeding cattle was higher than that in rearing calves, 44.3% of the positive cattle were infected with 2 to 5 species, and incidence of mixed infection was high in fattening cattle. 2. The rate of coccidal infection was 10.9%. Eimeria $z{\ddot{u}}rni$, Eimeria bovis and Eimeria bukidnonensis were mainly found in the examined cattle. The infection rates of cocidia in Holstein, breeding Korean cows, rearing Korean calves and fattening Korean cattle were 27.3%, 15.8%, 11.2% and 9.1%, respectively. 3. The rate of trematoda was 14.6% with Fasciola spp. (11.2%), Eurytrema spp. (2.0%), and Paramphistomum spp. infections (1.4%). Breeding Korean cows, fattening Korean cattle, Holstein and rearing Korean calves indicated 47.4%, 26.4%, 18.2% and 6.3% incidence of trematoda infections, respectively. of trematoda positive cattle, 76.6% were infected with Fasciola spp., 4. The rate of Theileria and Babesia infection was 62.7% in the examined cattle. Of these positive cattle 5.4% were infected with both parasites, 57.3% with Theileria, and 1.3% of rearing Korean calves and 22.6% of Holstein were found to have parasitized erythrocytes over 1.0%. 5. The incidence of diseases in 1968 cattle of 240 herds was 564 cattle (28.7%) of 154 herds (64.2%). of the diseases observed of skin occurred in 354 cattle (18.0%) of 61 herds (25.4%), diseases of respiratory system in 121 cattle (6.1%) of 34 herds (14.2%), diseases of digestive system in 38 cattle (1.9%) of 22 herds (9.2%), diseases of eye in 21 cattle (1.1%) of 13 herds (5.4%), diseases of urogenital system in 8 cattle (0.4%) of 8 herds (3.3%) and the other diseases in 24 cattle (1.2%) of 22 herds (9.2%). 6. Diseases of skin in 1968 cattle of 240 herds werds were observed in the highest incidence. Ringworm was observed in 13.3% of the examined herds, rearing Korean calves and Holstein showed high incidence. Scabies caused by Chorioptes bovis and alopecia localis along with infestation of lice (Damalinia bovis, Linognathus vituli) were observed in fattening Korean cattlein winter. 7. Diseases of respiratory system occurred frequently in rearing Korean cattle and Holstein. In the diseases of digestive system acute indigestion occurred in fattening Korean cittle, enteritis in rearing Korean calves and Holstein, and coccidiosis in rearing Korean calves maninly. 8. Infectious keratoconjunctivitis occurred in a fattening Korean cattle herd, sterility (2.0%) in breeding Korean cows, and theileriosis in Holstein calves were also occurred. In addition, poisoning and heat stroke were observed in several cattle.