The invention relates to a synthetic method for 2-methylallyl alcohol through a dehydration reaction of 2-methyl-1,3-propylene glycol. The synthetic method mainly overcomes the problem of low selectivity of 2-methylallyl alcohol in the prior art. According to the invention, a gas phase raw material containing 2-methyl-1,3-propylene glycol and an inertial diluent contacts with an alcohol dehydration catalyst in a fixed bed reactor and undergoes the dehydration reaction so as to produce a gas phase material containing 2-methylallyl alcohol; with such a technical scheme, the above-mentioned technical problem is overcome. The synthetic method provided by the invention is applicable to continuous industrial production of 2-methylallyl alcohol by using a fixed bed.