How long can a cockroach live without its head?

I don't know but people like to kill cockroaches, no one live them only with cutting head.

A cockroach can live for nine days without its head

a few hours. based on my observation.

now only heard about this.

Oh my god is it true that I can live for 9 days........

I think it can survive just for few minutes without head.

Interesting question..haven't observed a cockroach ..my knee jerk reaction would be to shout upon seeing a cockroach even if it is dead.

I don't think it can survive without head for that much time. May be for few hours. But not sure.

Only for a few days.

I think cockroaches can live for a week without their heads because they do not have vast circulatory system . They have open circulation system.

Cockroaches are infamous for their tenacity, and are often cited as the most likely survivors of a nuclear war. Some even claim that they can live without their heads. It turns out that these armchair exterminators (and their professional brethren) are right. Headless roaches are capable of living for weeks.
Here is the link that will throw more light : http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-cockroach-can-live-without-head

A cockroach is able to live for two weeks without head.