A process for preparing cyclohexanol and cyclohexanone by cyclohexane oxidation, comprising steps of: firstly processing uncatalyzed oxidation on cyclohexane by molecular oxygen, in such a manner that an oxidized mixture with cyclohexyl hydrogen peroxide serving as a primary product is generated; then decomposing the cyclohexyl hydrogen peroxide to produce cyclohexanol and cyclohexanone; and then rectifying to obtain a cyclohexanol product and a cyclohexanone product; wherein the step of decomposing the cyclohexyl hydrogen peroxide utilizes a three-step decomposition process combining a homogeneous catalytic decomposition process of bis(tert-butyl) chromate with a heterogeneous catalytic decomposition process of sodium hydroxide alkaline aqueous solution, comprising steps of: performing the homogeneous catalytic decomposition by utilizing the bis(tert-butyl) chromate as a catalyst, and adding 1-hydroxy ethidene-1, 1-diphosphonic acid (di)octyl ester, wherein adding amount of the 1-hydroxy ethidene-1, 1-diphosphonic acid (di)octyl ester for serving as a scale inhibitor is equivalent to adding amount of Chromium which is an active component of the catalyst, the decomposition temperature is at a range of 90±10°C, the decomposition pressure is at an atmospheric pressure, and the reactor residence time is at a range of 24∼26 minutes; performing the heterogeneous catalytic decomposition in the sodium hydroxide alkaline aqueous solution under low alkalinity, wherein the low alkalinity means that a molar concentration of OH- is at a range of 0.2∼0.8mol/L; and performing the heterogeneous catalytic decomposition in the sodium hydroxide alkaline aqueous solution under high alkalinity, wherein the high alkalinity means that a molar concentration of OH- is at a range of 0.9∼2.2mol/L. firstly processing uncatalyzed oxidation on cyclohexane by molecular oxygen, in such a manner that an oxidized mixture with cyclohexyl hydrogen peroxide serving as a primary product is generated; then decomposing the cyclohexyl hydrogen peroxide to produce cyclohexanol and cyclohexanone; and then rectifying to obtain a cyclohexanol product and a cyclohexanone product; wherein the step of decomposing the cyclohexyl hydrogen peroxide utilizes a three-step decomposition process combining a homogeneous catalytic decomposition process of bis(tert-butyl) chromate with a heterogeneous catalytic decomposition process of sodium hydroxide alkaline aqueous solution, comprising steps of: performing the homogeneous catalytic decomposition by utilizing the bis(tert-butyl) chromate as a catalyst, and adding 1-hydroxy ethidene-1, 1-diphosphonic acid (di)octyl ester, wherein adding amount of the 1-hydroxy ethidene-1, 1-diphosphonic acid (di)octyl ester for serving as a scale inhibitor is equivalent to adding amount of Chromium which is an active component of the catalyst, the decomposition temperature is at a range of 90±10°C, the decomposition pressure is at an atmospheric pressure, and the reactor residence time is at a range of 24∼26 minutes; performing the heterogeneous catalytic decomposition in the sodium hydroxide alkaline aqueous solution under low alkalinity, wherein the low alkalinity means that a molar concentration of OH- is at a range of 0.2∼0.8mol/L; and performing the heterogeneous catalytic decomposition in the sodium hydroxide alkaline aqueous solution under high alkalinity, wherein the high alkalinity means that a molar concentration of OH- is at a range of 0.9∼2.2mol/L. performing the homogeneous catalytic decomposition by utilizing the bis(tert-butyl) chromate as a catalyst, and adding 1-hydroxy ethidene-1, 1-diphosphonic acid (di)octyl ester, wherein adding amount of the 1-hydroxy ethidene-1, 1-diphosphonic acid (di)octyl ester for serving as a scale inhibitor is equivalent to adding amount of Chromium which is an active component of the catalyst, the decomposition temperature is at a range of 90±10°C, the decomposition pressure is at an atmospheric pressure, and the reactor residence time is at a range of 24∼26 minutes; performing the heterogeneous catalytic decomposition in the sodium hydroxide alkaline aqueous solution under low alkalinity, wherein the low alkalinity means that a molar concentration of OH- is at a range of 0.2∼0.8mol/L; and performing the heterogeneous catalytic decomposition in the sodium hydroxide alkaline aqueous solution under high alkalinity, wherein the high alkalinity means that a molar concentration of OH- is at a range of 0.9∼2.2mol/L.