The finite element model was used to simulate the temperature distribution of a arrayed vertical-cavity surface-emitting laser (VCSEL). In this work, the dimension of AlGaAs/GaAs based VCSEL array was active diameter and pitch, and AuSn solder of 80wt%Au-20wt%Sn was included to flip-chip bond. The results of the thermal simulation will be applied to predict the thermal cross-talk in high speed parallel optical interconnects.