Conservative workers have been wiping off the offending moustaches around the clock.
James Morris slammed those responsible.
He said: "It's a shame that some mindless individuals have decided to vandalise my posters.
"It's a pity that they have to resort to this when we should be focussing on the issues of the campaign: securing a brighter future for Halesowen & Rowley Regis, creating more local jobs and skills and protecting local health services like Rowley Regis Hospital."
The Chancellor George Osborne, in the constituency today, said: "This shows that our opponents have lost the argument.
"People now have the choice between a strong MP like James who has helped bring down unemployment or chaos with Ed Miliband being told what to do by the SNP."
"The fact is the posters are not vote winners because Mr Morris looks like an evil Nigel Havers in them anyway."
Other Conservative politicians across the country have also had Hitler moustaches drawn on their posters.