With the rapid development of mobile Internet, the business volume continues to increase, which puts forward higher requirements for carrying network. As the current mainstream load carrying network scheme, IPRAN network conforms to the load carrying requirements of various services, not only adapting to base station transmission, but also compatible with multi-service comprehensive transmission. Different networking schemes will lead to great differences in cost. How to design the lower cost IPRAN networking scheme rapidly while meeting the business requirements has always been the concern of telecom operators. This paper presents a cost optimization scheme based on IPRAN networking. Based on the actual situation of BBU and RRU distribution in the region to be planned, we designed the access scheme for RRU with the aim of minimizing the sum of lines between BBU and RRU, so as to ensure the lowest line cost. In addition, we propose two constraints, namely, the number of comprehensive service access nodes on each comprehensive service access ring and the number of centralized BBU on each comprehensive service access node. Under the two constraints, we choose the scheme with the lowest equipment cost. Finally, we conducted simulation on the algorithm proposed in this paper, and the results showed that: for IPRAN networks with less than 1000 base stations, this algorithm could select the scheme with the lowest equipment cost from many schemes within 0.7 seconds, and meanwhile give the line design scheme with the least optical fiber loss, providing reference for IPRAN network.