The invention discloses a first-order inertia force balance mechanism of a single-row reciprocating compressor. The first-order inertia force balance mechanism comprises a compressor crankshaft; a coaxial driving gear is arranged on the compressor crankshaft; balance weights equal in mass are arranged in the reverse directions of two cranks on the compressor crankshaft; the mass of each balance weight is m0; the mass of the two balance weights multiplied by the radius r0 of the balance weights equals one half of the amplitude of the reciprocating inertia force; driven gears are symmetrically arranged on the two sides in the radial direction of the coaxial driving gear; the diameter, the modulus and the tooth number of each driven gear are the same as the diameter, the modulus and the toothnumber of the coaxial driving gear; two balance masses with the mass of m00 are arranged on the two driven gears in the radial direction; and the following equations are met: 2r0m0+4r00m00=rms, and r0m0=2r00m00. According to the first-order inertia force balance mechanism, the simple structures of the balance weights and the balance masses are arranged, and therefore the single-order reciprocating inertia force of the single-row compressor can be completely balanced to be zero with very low cost.