Abstract: Network reliability is one of the most important performance in the design of Virtual Network (VN) and gaining more and more attention currently. This paper focuses on the issue of less stringent reliable virtual network mapping. The VN topology remains connected except failed virtual node in the event of single substrate node failure without reserving backup resources. The necessary conditions for mapping VN to be reliable are researched at first, and then the issue is formulated as an Integer Linear Program (ILP) based on it. Finally a novel heuristic algorithm is proposed to solve it. The policy consists of a topology-aware node mapping strategy and a link mapping strategy based on tabu search. Evaluation results show that the proposed heuristic algorithm can obtain the reliable VN mapping with higher substrate long-term average revenue and efficient resource utilization.