ON THE BRST OPERATOR STRUCTURE OF THE N=2 STRING

The BRST operator cohomology of N = 2 two-dimensional supergravity cou pled to matter is presented. Descent equations for primary superfields of the matter sector are derived. We find one copy of the cohomology at ghost number one, two independent copies at ghost number two, and c onjecture that there is a copy at ghost number three. The N = 2 string has a twisted N = 4 superconformal symmetry generated by the N = 2 su perstress tensor, the BRST supercurrent, the antighost superfield, and the ghost number supercurrent.