I take it the field is numeric?
When you say suppress, do you mean you don't want zero to show up at all?
or you just want it to be 0.00 (as it appears you are trying to do with your
formatting).
If you just want to suppress it entirely, you can always change the query
that serves as the report recordsource.
find the field that returns the zero (let's call it FieldA) and change it to:
iif(FieldA=0,"",FieldA) As NewFieldA
if you go this route, you'll have to change the data source for the field on
your report (it used to be FieldA, it now would be NewFieldA).