The invention provides a drilling fluid suitable for tight sandstone reservoirs. In terms of mass percentage, the composition of the drilling fluid includes: 0.5%-2% bentonite, 0.5%-2.5% coating inhibitor, 0.5%-1% flow regulator, 3%-4% filter reducer Lost agent, 0.4%-0.8% waterproof locking agent, 4%-10% temporary plugging agent, 40%-50% biological polyalkoxide, 0%-50% weighting agent, and the balance is water. The density of the liquid is 1.16g / cm3-1.55g / cm3. The drilling fluid suitable for tight sandstone reservoirs provided by the invention can effectively prevent the pollution of tight sandstone reservoirs and ensure the safety of downhole operations.