Eddy current testing (one of the non-destructive testing-NDT) is used to investigate heat exchanger tubes and detecting any possible faults in these tubes. Main aims of this paper determine the optimum design of a probe in order to improve sensitivity and inspection system performance. Firstly, this paper presents equations related to designing and characteristics of the probe to investigate sample tubes. Then, optimum design is presented in order to reach the highest signal to noise ratio (SNR) and sensitivity (S) using Bees Algorithm-BA. Finally, eddy current testing is performed for optimum probe using finite element analysis (FEA).