On the basis of the property and features of equideviate matrixes

a novel method for constructing Quasi-Cyclic LowDensity Parity-Check（QC-LDPC）codes is presented in this paper.The LDPC codes constructed in this method are easy for effective encoding and decoding

have good girth properties and can avoid the girth-4effectively

which prevents the generated codes from short cycle interference.Furthermore

it can save the storage space in terms of hardware implementation.The simulation results show that when the bit error rate reaches 10-7

the net coding gain of the high code-rate QC-LDPC（3780

3542）constructed this way is improved by about 2.1dB as compared with that of the RS（255

239）code in ITU-T G.975

proving that the code has a better error correcting performance

and by 0.35dB as compared with that of regular QC-LDPC（4221

3956）code.