— Failure-Rate Minimization is becoming one of the major design issues in wireless sensor network (WSN) architecture due to multiple available Functional-units (FUs). There is a tradeoff between reliability and performance, such as timing constraint. This paper studies how to minimize the total failure rate while satisfying performance requirement for WSN applications. Two novel algorithms are proposed to solve the FRMFS (Failure Rate Minimization with FU Scheduling) problem. We use these FU scheduling algorithms to minimize system failure rate without sacrificing performance. Our results show that the average improvement on failure-rate reduction is significant with the use of our algorithms.