Given a signed graph
![$\dot{G}$](img53.png)
, let
![$A_{\dot{G}}$](img54.png)
and
![$\smash{D^{\pm}_{\dot{G}}}$](img55.png)
be its standard adjacency matrix and the diagonal matrix of vertex net-degrees, respectively. The net Laplacian matrix of
![$\dot{G}$](img53.png)
is defined to be
![$\smash{N_{\dot{G}}=D^{\pm}_{\dot{G}}-A_{\dot{G}}}$](img56.png)
. In this paper we give some spectral properties of
![$N_{\dot{G}}$](img57.png)
. We also point out some advantages and some disadvantages of using the net Laplacian matrix instead of the standard Laplacian matrix in study of signed graphs.