I imagine you're talking about your death at work benefit. Not a very good idea at all. That is becuse you could lose your job, fingers crossed, and then you'd have zero cover and have the added headache of being older and finding it nigh on impossible to get life cover at a reasonable price (due to age/health problems)
How much is your mortgage, how much is the insurance. What type is it?
What you can do is switch to 'term' insurance, this is the type that reduces each year in line with your mortgage reduction and is the cheapest type of insurance. With your work benefits this is most likely all you need. But it does also depend on your family situation.