The invention discloses a compressor and a crankshaft assembly therefore. The crankshaft assembly of the compressor comprises a lower flange, a crankshaft penetrating through the lower flange and a supporting piece which is connected with the tail end of the crankshaft and supports the crankshaft; a first gap is formed between the crankshaft eccentric part of the crankshaft and the lower flange. According to the crankshaft assembly of the compressor, the supporting piece connected with the tail end of the crankshaft is adopted for supporting the crankshaft, the lower flange is not needed for supporting the crankshaft, the first gap is formed between the crankshaft eccentric part of the crankshaft and the lower flange, the crankshaft cannot make contact with the lower flange when the crankshaft jumps up and down, and therefore the situation that the crankshaft impacts the lower flange is effectively prevented, and then noise of the compressor is reduced.