A 2D-axisymmetric finite element analysis (FEA) model was built to simulate an optical fiber-based photoacoustic generator. A layer of absorbing film deposited on the tip of an optical fiber converts the pulsed-laser energy into vibrations, which excite broadband ultrasound waves in the adjacent fluid. Instead of 1D or simplified 2D theoretical solution, this multi-physics FEA model successfully calculates the ultrasound generated by film vibration and fluid heating. Another advantage of this numerical calculation is that the dimensions of fiber and film can be optimized to achieve high photoacoustic conversion efficiency. Two major conclusions were obtained from the simulation: 1) Thicker absorbing film has higher photoacoustic conversion efficiency than thinner film; 2) Shorter laser pulse leads to higher conversion efficiency and higher ultrasound central-frequency. The FEA results provide a practical support to the design of this type of optical fiber photoacoustic generator, and make it possible to have a miniaturized non-destructive testing transducer in the intravascular and intraluminal applications.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.