SRAM-based FPGAs have been widely used in space engineering. However, the configuration memory in SRAM-based FPGA is susceptible to the single event effects (SEE). It can disrupt the communication or control functions of the spacecraft. To mitigate SEE effects of the SRAM-based FPGAs used in space radiation environment, Beijing Microelectronics Technology Institute (BMTI) developed a 300 thousand gates Single Event Effect hardened SRAM-based FPGA -- BQVR300RH. The BQVR300RH employs Radiation Harden by Design (RHBD) technique. Hardened standard cell library based on Adaptive SRAM (ASRAM) structure is established. For especially sensitive and important resource, other assistant techniques are also adopted. The experiment results show that the BQVR300RH improved the anti-SEU characteristic a lot, compared with Xilinx 300 thousand gates space-grade SRAM-based FPGA (XQVR300). The SEU threshold of BQVR300RH is 19.06 MeV⋅cm2/mg. The anti-SEU characteristic improves three orders of magnitude than XQVR300. The improvement of anti-SEU behavior expands the usage of SRAM-based FPGA in aerospace applications. Currently, BQVR300RH has been used in space field in China.