The photoacoustic technology has attracted extensive attention because of its high spatial resolution of sound source and easy generation. However, due to the low efficiency of photoacoustic conversion, how to use multi-point photoacoustic to generate acoustic focusing has become an important way to improve the sensitivity of photoacoustic detection. In order to use the multi-point photoacoustic to generate acoustic focusing to improve the sensitivity of photoacoustic detection, the study on photoacoustic focusing based on eight-element array is carried out in this paper. The effects of spatial excitation position, frequency and number of the array elements on the photoacoustic focusing performance are analyzed with the time reversal method based on the simulation and experimental methods. The experimental results show that a focusing effect of great than 10 times has been obtained.