Pseudo Noise sequences (PN) are widely used in telecommunications and for measurement purposes. In this paper, cross correlation results of PN family codes: Gold, Kasami sequences are shown. PN sequences have random like properties that help in reducing the correlation among speech samples. In Spread Spectrum CDMA system each user is assigned a pseudo noise sequence for the purpose of spreading as well as de-spreading. The maximal length PN-sequence (m-sequence) is the best-described PN-sequence whose length is equal to its period. Various PN-codes can be generated using Linear Feedback Shift Register (LFSR). All the results presented here were tested and simulated via MatLab programs.