Hematologic and serum biochemistry values were evaluated in free-ranging, wild Norwegian reindeer (Rangifer tarandus tarandus) as part of a reintroduction program in southwestern Norway in November 1995 and 1996. Animals were immobilized with medetomidine-ketamine by dart from a helicopter. Blood was drawn for serum chemistry from 31 adults (nine males and 22 females) and for hematology from 29 adults (eight males and 21 females). Significant differences (P<0.05) were found between male and female results for alkaline phosphatase, selenium, and zinc. Although there was a significant difference between male and female gamma-globulin values and the total albumin:globulin ratio, the overall values are much lower than those reported for other Rangifer species. Sexual differences should be interpreted with caution due to the low number of males compared to females. References ranges are presented combining male and female results for hematology and serum chemistry and separately for males and females for serum electrophoresis. No correlation was found between induction time and aspartate transaminase, creatine kinase, glucose, cortisol, or total protein. Blood values were generally similar to those published for semidomestic reindeer (Rangifer tarandus tarandus) and free-ranging caribou (Rangifer tarandus caribou), but the effect of capture drugs, stress, season, and sample size should be considered with interpretation. This paper provides the first report of baseline hematologic and serum biochemistry reference ranges for free-ranging, wild Norwegian reindeer during early winter.