A fuzzy clustering model is presented considering the uncertainty of transformer fault diagnosis,and a matrix eigenvalue analysis method is proposed to estimate the correct number of clusters which can implement the unsupervised fault diagnosis. Aiming at the problem existed in fuzzy c - means clustering algorithm which is applied to transformer fault diagnosis, seeker optimization algorithm ( SOA) is introduced to obtain the optimized initial clustering center. SOA simulates human random search behavior and overcomes the defects of particle swarm optimization ( PSO) and genetic algorithm ( GA) with local search and poor convergence. Simulation results show that SOA has a higher convergence speed and a better global searching ability. Comparing with the traditional intelligent optimization algorithms,SOA is more effective and robust,which can give a reference for transformer fault diagnosis.