Economic and productive data from Polish arctic fox farming were used to develop a bio- economic deterministic model simulating an average fox farm. The model was used to estimate economic weights for 4 economically important traits: body size - BS, fur quality - FQ, colour type - CP and litter size - LS. A 10-year investment period and two alternative discount rates: 0 and 6% were assumed when computing the number of discounted expressions (NDE). Marginal economic values (MEV) were estimated per one female purchased. Highest MEV were derived for LS (88.304 PLN), followed by FQ (86.548 PLN) and BS (39.024 PLN). Much lower MEV (10 times lower than for BS and 20 times lower than for LS and FQ) was estimated for CT (3.944 PLN). The relative economic weights derived for the alternative of 0% interest rate per year were 0.48 for LS, 0.15 for BS, 0.35 for FQ and 0.02 for CT, and were comparable to those estimated for the situation of 6% interest rate per year (0.46, 0.15, 0.36 and 0.03, respectively).