My husband dies this and and I am receiving his Social Security survivor benefits. I just received an Insurance check from Sun Life, will this check affect my SSI benefits.
I'm sorry for your loss.
Just to clarify my answer, I'm assuming that you don't mean that you are receiving Supplemental Security Income (https://www.ssa.gov/ssi/) when you refer to SSI benefits. Supplemental Security Income (SSI) is a needs based program administered by the Social Security Administration, and insurance proceeds can affect a person's SSI payments.
However, insurance proceeds do not affect Social Security benefits. So, provided that you are only receiving Social Security benefits, the insurance check you received will not affect your benefits.