The invention discloses compound polyvinyl alcohol drilling fluid for marine hydrate reservoirs, and relates to the field of natural gas hydrate mining. The drilling fluid is prepared from the following components: polyvinyl alcohol, sodium chloride, methyl alcohol, ethylene glycol, sulfonated phenolic resin SMP-2, potassium humate, xanthan gum, polyvinyl caprolactam, polyvinyl methyl ether, tetra-n-hexyltrimethyl ammonium bromide and prepared water, can be applied to drilling of submarine natural gas hydrate reservoirs, and has the characteristics of freeness from solid phase and low temperature resistance; a kinetic inhibitor and a synergist are added into the drilling fluid for compounding, so that the drilling fluid has a better hydrate generation inhibition effect; moreover, the drilling fluid components have little harm to the environment, so that the drilling fluid has the advantages of high efficiency, environmental friendliness, cheap and readily-available raw materials and the like.