A titanium silicalite molecular sieve with a hierarchical porous structure is provided. The spectral peaks of the 1H MAS NMR spectrum of the titanium silicalite molecular sieve in the chemical shift range of 1-6 ppm are separated to obtain five spectral peaks whose chemical shifts corresponding to the peak positions are 1.8±0.1 ppm, 2.2 ppm±0.1 ppm, 2.8 ppm±0.1 ppm, 3.8±0.1 ppm and 4.6±0.1 ppm, respectively. The peak areas of the peaks satisfy specific proportional relationships. The molecular sieve has significantly enhanced anti-deactivation performance and can significantly improve the cyclohexanoneoxime conversion rate and the caprolactam selectivity when used in the cyclohexanoneoxime gas-phase Beckmann rearrangement reaction.