Meshless method has advantages in analyzing the deformation around a crack. However, the effectiveness of such method is influenced by the treatment of local support domain which is a base for an appropriate selection of field nodes in the construction of shape functions. In the current practice, the methods to determine support domain have some drawbacks. It is therefore beneficial to develop a more flexible technique for determining the support domain in crack simulation. This paper presents such a technique which could be used in both regularly and irregularly distributed nodes. Numerical examples show that the technique produces accurate results in these two situations. Moreover, the new technique can be integrated with different types of meshless methods to provide an effective way in handling arbitrary nodal distribution to meet the needs of solutions to problems with complex geometric boundaries.