A method for making xanthan gum copolymer nanomicelles comprising: 1) degrading xanthan gum in aqueous solution to obtain degraded xanthan gum; 2) preparing xanthan gum bromide from the degraded xanthan gum; 3) preparing xanthan gum copolymer from the xanthan gum bromide and 4) making the gum copolymer nanomicelles from the xanthan gum copolymer. The xanthan gum copolymer nanomicelles have good morphological regularity, good biocompatibility and stable performance as an anticancer drug carriers.