Fine processing of sapphire material is quite difficult because of its high hardness, low thermal conductance and fragility. Through analyzing and discussing the features of picosecond pulse laser for dicing of sapphire substrates, the parameters of the laser dicing have been researched in the process of sapphire components and parts for infrared focal plane array packaging, and a series of optimized parameters have been obtained. For the sapphire transition electrode plate with a thickness of 0.4 mm commonly used in infrared focal plane array packaging, the best dicing effect is achieved when the combined dicing parameter is P(100)X(0.01/20) Y&Z(12) Z(0.1/3). The influence of the change of laser power parameters on dicing is analyzed, and some problems in the actual dicing operation are discussed.