ASLR and other defense measures have been deployed in modern computers against memory data leakage and control flow hijacking, which are two common vulnerability exploitation methods, but attackers can always bypass these security defense mechanisms to attack the computer. For the problem of the randomization strategy in ASLR technology is partial-oriented memory space. This paper presents a heap randomization strategy for the entire heap memory space. By changing the access order of memory pool, the strategy reduces the time consumption of memory region search, a random memory block allocation algorithm is proposed to increase the unpredictability of heap memory addresses and improve the security of computer systems. The randomization algorithm increases the variation interval of memory block gap by adding randomization parameters, then through the attack experiment and time performance experiment, the appropriate randomization parameters are determined to ensure the efficiency of the algorithm.