The invention discloses a method for improving temperature distribution in a process of single crystal casting solidification, relating to the field of high-temperature alloy directional solidification. In a process of preparing molten mould casting ceramic mould shell, and in a process of implanting a heat conductor into a casting to be solidified and transfer heat to the external, a position with thermal barrier is easy to occur. The heat conductor is graphite or SiC. Practical use shows that by applying the technology, an undercooling difference and an undercooling time difference in the casting can be greatly reduced, thereby the probability of generating stray crystals is obviously reduced, and the single crystal qualified rate of the casting is greatly enhanced.