Common polygenic diseases result from compounded risk contributed by multiple genetic variants, meaning that simultaneous correction or introduction of single nucleotide variants is required for disease modeling and gene therapy. Here, we show precise, efficient, and simultaneous multiplex base editing of up to three target sites across 11 genes/loci in cynomolgus monkey embryos using CRISPR-based cytidine- and adenine-base editors. Unbiased whole genome sequencing demonstrates high specificity of base editing in monkey embryos. Our data demonstrate feasibility of multiplex base editing for polygenic disease modeling in primate zygotes.