Linear wireless sensor network (LWSN) is widely used to monitor key infrastructure in linear topology such as railways and natural gas pipelines, whose reliability is very important, and coverage is an important indicator to measure reliability. Currently, most methods for evaluating the LWSN coverage are based on a 0/1 disk sensing model, but in practice, the monitoring reliability of sensors follows a probability distribution with the increase of coverage radius. Therefore, a reliability analysis method based on a probabilistic sensing model is proposed, which can calculate the effective sensing range based on the physical parameters of sensors, thereby improving the accuracy of evaluation. To reduce the size of the system state space, a binary decision tree is used to construct the LWSN system state set. In this study, the failure probability of nodes is assumed to follow a Weibull distribution, and simulation experiments are conducted for different communication radii and sensing ranges. The results show that this method can effectively evaluate the reliability of LWSN, and the evaluation accuracy is more accurate than the 0/1 disk sensing model.