No, you can't break your lease for this reason. You can only break your lease without consequences (i.e. without still be liable for the rent) if the *landlord* breaches the lease in some material (important) way. (The lease is a contract between you and the landlord; a contract can only be safely terminated for the violation or breach of one of the parties, not for the actions of someone not a party to your lease/contract.) But what you describe is an action by a fellow tenant, so the landlord is not liable or responsible for it. There are times when IF another tenant is engaged in "disorderly conduct"--loud parties late at night; harassing other tenants; etc.--and the landlord refuses or fails to take any steps to remedy the situation, that would count as sufficient grounds to terminate the lease for denial of quiet enjoyment. However, that is only the case if the offensive conduct is something which the landlord may legally take action about, like disorderly conduct; however, the natural or common sounds of apartment living--the sounds of someone walking in the unit overhead; the sounds of children playing; or, as here, snoring--even if somewhat louder than normal, is still considered by law to not be disorderly but rather to be simply an incident of apartment living. The landlord cannot evict someone for, for example snoring; and since the landlord cannot evict for this, he has no power over it, which means he is not resonsible for it and you cannot escape your lease. You may need to instead consider earplugs, a white noise machine, etc., unfortunately.