The invention discloses preparation of cellulose carbamate and a low-temperature dissolution spinning method of the cellulose carbamate. The method comprises the following steps: adding cellulose into a sodium hydroxide solution, stirring uniformly, immersing, taking out the cellulose, washing with water to a neutral state to obtain alkalified cellulose, adding urea, stirring uniformly, putting in a drying oven, heating, reacting and drying to obtain the cellulose carbamate; pulverizing the cellulose carbamate into powder, adding the powder into a mixing kettle, adding double solvents of sodium hydroxide, thiocarbamide and deionized water, and stirring uniformly; and carrying out extrusion, deaeration and filtration on the raw material in the mixing kettle, spraying by spinneret orifices of a spinneret, sequentially sending into a first coagulation bath and a second coagulation bath to obtain a solid, washing with water in a water tank, and carrying out stretching and winding by a spinning component to obtain the cellulose carbamate fiber. The method is suitable for preparing the cellulose carbamate by an industrialized large-scale production process route, and has important meanings for implementing low-temperature dissolution spinning engineering and industrialized production of cellulose.