Scientific  research   has  demonstrated  that  different   compounds containing copper are capable  of stimulating  body weight  gains,  improving  the  health  of animals and  attaining high production performance without  causing excessive accumulation of various  chemical compounds in  animal   tissues. Besides, copper has  been  reported  to exert  a  positive  effect on  the immune  system,  haematological  blood markers  and  the  microbiological balance  in the gastrointestinal tract  of turkeys. The  experiment  was conducted on 60 BUT-9 line turkeys. The  birds  were  divided  into 5 experimental groups.  Each  group included 12  turkeys kept  in  cages.  The bird  were  reared  for  19  weeks.  The  first   group served  as  control. Group II received  CuS04 added  to water  in  a  dose of 10  mg Cu  dm-3  H20. Group III was  com posed of birds  administered a Cu  chelate  with  lysine   in  a dose of 10  mg  Cu  dm-3  H20.  Group  IN  received  CuS04 in  a  dose of 20 mg Cu  dm-3 H20,  whereas  group N were  given  a  Cu-lysine   supplement  in a  dose of 20  mg Cu  dm-3  H20.  The birds  were  fed commercial  complete feed mixes.  The copper preparations were  added to drinking water  since  the 3rd  week of rearing. The  objective  of this  study  has  been to determine  the effect  of Cu supplementation in  the  organic  and  inorganic  form and  in two doses on the health  of birds  and  on accumulation of mi- nerals   in  their  breast  muscle and liver.   Further  analyses involved  the  determination of haematological  and biochemical  markers in  blood as  well  as  assays  of selected  minerals in  the birds'  blood, breast  muscle  and  liver.   The analysis of the  results   indicated  that the doses  of copper  improved  the health   of the  turkeys, as  verified   by  better haematological markers. Statistically  significant difference  appeared  in  the  group receiving  20  mg Cu  dm-3 H20  irrespective of the  chemical  form  in which  copper was administered. The  study  also shows  that  Cu  supplementation   has  a significant  effect  on  the  metabolism  of lipids   and a nonsignificant impact on the content  of mineral elements  in the  analyzed  tissues.  It was not until the 20 mg dose of Cu  as  a chelate  had  been applied  that  the accumulation of copper  in the  turkey's liver  was  enhanced.