By e.m.f. measurements of concentration chains of type (–) YbТe (solid) | liquid electrolit, Yb^{3 +} | (Yb–Bi–Тe) (solid) (+) in the 300–400 К temperatur interval the system Yb–Bi–Te in YbTe–Bi₂Te₃–Te composition area is studied. The solidphase equilibriums diagram is constructed and partial thremodynamic properties (PTP) of YbTe in alloys are calculated. By a combination of the received data with thrermodynamic  functions YbTе and Bi₂Tе₃ the PTP of ytterbium in alloys and standard integral thermodynamic functions of ternary compounds YbBi₄Те₇ (–=485.9±4.0 kJ mole^-1, –= 487.9±4.7 kJ mole^-1, =631±26 J К^-1 mole^-1) and YbBi₂Те₄ (400.8±2.3, 398.2±3.8, 383±18) are calculated.