In this paper we present a novel method of gas leakage detection based on self-mixing interference with an extremely compact Er3+-Yb3+ codoped Distributed Bragg Reflector (EYDBR) fiber laser. According to the simulation and theoretical analysis of gas leakage of tank, we infer that the vibration frequency peak of tank caused by gas leakage increases with the internal pressure. In the experiment, the results agree with the theoretical prediction and the relevance of polynomial fitting about the spectrum peak of tank vibration and internal pressure is 0.99725. Thus, we can get the internal pressure of tank by measuring the vibration frequency peak of tank. Moreover, it has important significance in the prevention of the accident of flammable or explosive gas leakage. (C) 2014 Elsevier B.V. All rights reserved.