 His clan was a prominent one in the Sanfu (三輔, greater Chang'an) region, and both his grandfather Wei Zhenxi (韋真憙) and father Wei Xu (韋旭) were commandery governors during Northern Wei.In Wei Xiaokuan's youth, he was described to be studious and calm.When the general Xiao Baoyin rebelled in 527 and seized the Chang'an region, he was at the capital Luoyang, and he volunteered to serve in the army against Xiao.