For the first time, we use a gate-switching resistance memory to implement the TRNG (True random number generator). First, a resistance memory was built on a FinFET platform, named RG-FinFET(resistive-gate) RRAM which was simply an MIM(metal-insulator-metal) integrated on top of the FinFET gate. It performed as a novolatile memory (NVM) which used resistance switching to distinguish 0 and 1 states through the drain current of the FinFET. The experimental results show that RG-FinFET exhibits high SET speed of 50ns at 3.4V/RESET speed of 10ns at 2.4V, read time as small as 16ns at 1.1V. Furthermore, excellent 107 cycles endurance and data-retention under 125°C for over one month can be achieved. The array-level performance is also analyzed, showing well disturbance-immune during SET, RESET and read. Secondly, a TRNG was developed based on the drain current variation of RG-FinFET. In terms of the security, this TRNG exhibits ideal un-biased normal distribution of hamming distance, and narrow distribution of hamming weight. Moreover, we introduced the concept of XNOR-enhanced operation to TRNG at high temperature to enhance its uniformity. In NIST test, this TRNG passed all items. More importantly, this work is ready for an embedded FinFET technology to develop TRNG with full logic CMOS compatibility.