The wide application of reciprocating compressor is limited by their high vibration and acoustic noise. This study is aiming for design and analysis of the dynamic balancing counterweight (so-called sprung mass) for practical vibration suppression of reciprocating compressors. First, an analytical method for computing the counterweight of the crank and the force of the crankshaft connecting rod system is established and computerized. Use of structural finite element method and elasticity theory, 3D vibration modes and resonant frequencies of a 2 hp commercialized reciprocating compressor with single cylinder is analysed via numerical and experimental simulation within 6% error. Different geometric size design of the crank is proposed for bettering implementation.