Isobutylene production method

The invention relates to an isobutylene production method and mainly solves the problems of low isobutylene yield and high solvent consumption in the prior art. The isobutylene production method includes: using methanol as both an efficient absorbent to absorb-desorb, separate and remove light components below C3 in product gas and a raw material to be in MTBE (methyl tert-butyl ether) etherification reaction and cracking reaction with mixed carbon four containing isobutylene to obtain a high-purity isobutylene product. Therefore, purity of isobutylene is greater than or equal to 99.9%; once through yield of isobutylene is greater than or equal to 98.5%, consumption of methanol is less than or equal to 1.5%; the above problems are solved well, and the isobutylene production method can be applied in production for preparing isobutylene.