The aim of this research was to determine if the age of healthy subjects older than 40 years of age has an influence on the concentration of β(2) -microglobulin in the serum of subjects of different populations. We examined the values of β(2) -microglobulin in the serum of 51 healthy subjects aged 40-86 years using the microparticle enzyme immunoassay AxSYM β(2) -microglobulin test. The reference values of β(2) -microglobulin according to the nonparametric statistical method is 0.95-2.73 mg/L. A correlation was found between β(2) -microglobulin and age: 40-50 years (0.94-1.54 mg/L), 51-65 years (0.96-2.62 mg/L), and >65 years (1.13-2.84 mg/L). There was no significant statistical difference of β(2) -microglobulin between genders (P > 0.05); however, there was a statistically significant difference between the concentration of β(2) -microglobulin and the subjects' age. (Spearman's rank correlation coefficient ρ = 0.66; P < 0.01). A direct correlation between age and the concentration of β(2) -microglobulin was observed. This research is a contribution to determining reference values of β(2) -microglobulin in subjects of different populations.