The invention discloses a preparation method for a sodium stannate product with the whiteness larger than 95 degrees. The preparation method includes the following steps of leaching crude sodium stannate, wherein crude sodium stannate, NaOH and water are heated to react; adjusting the alkali content by adding NaOH; oxidizing, wherein hydrogen peroxide is slowly added into the prepared solution to react until the specific gravity of the solution is 1.5 g/m<3>, and heating is stopped; settling, wherein the solution stands until solid and liquid are layered obviously; secondary settling, wherein supernate is taken out and stands for settling; filtering, wherein the supernate is extracted to a filtering disc, and hydrogen peroxide is added to carry out circulating filtration; concentrating and crystallizing, wherein vacuum concentration is carried out on the filtered solution, and concentration is stopped when the specific gravity of the solution reaches 1.7 g/m<3>; solid-liquid separating; obtaining the sodium stannate product with the whiteness larger than 95 degrees through drying. The whiteness of the sodium stannate product is improved through leaching oxidization, filtering oxidization and drying oxidization, the sodium stannate product with the whiteness larger than 95 degrees can be obtained through preparation, and the cognition degree to the product by clients is effectively improved.