The invention pertains to the agricultural field, in particular to a water saving and production increase cultivation method of plastic-film covering peanut in a poor dry land. The method includes sowing in a flat field, ridges formed by covering soil after sowing, fertilizer application, and covering films. Prior to rainy season, straws of plants are used for covering ridges and furrows which are sprayed by acetochlor herbicide before covering. The method can reduce the rain runoff of soil, reduce the water evaporation volume in the soil cultivation layer, and improve the utilization rate and pod output of peanut, thus realizing the objective of water saving and production increase.