In the FDMA and TDMA Cellular Systems, call blocking rise when frewquence slots andtime slots are used to ther users. Otherwise, in the CDMA cellular systems, call locking arises when interference level is above 10dB according to call of other users. System capacity is defined to be Erlang capacity that is the number of users when CDMA blocking probability is 1% or 2%. Users number corresponded channel number of AMPS and TDMA cellular systems. In this paper, we proposed new reuse-fraction using square of interference poser and obtained Erlang capacity for reverse link of CDMA cellular system with bit rate $R_{b}$, 9.6kbps and 14.4kbps. As a results, Erlange capacity of CDMA system have more 20.7 and 5.5 times than AMPS and TDMA system and have more form 1 to 4 Erlang thatn Viterbi and Padovani obtaned.d.