Though accurate laboratory studies of malononitrile (CH2(CN)2), a dinitrile molecule, have been carried out from time to time, and it has large electric dipole moment $$\mu = 3.735$$ D, its detection in a cosmic object is still awaited. Because of two equivalent hydrogen atoms, it has ortho and para species. In order to obtain information about some potential spectral lines of malononitrile, which may play important role for its identification in a cosmic object, we have carried out Sobolev large velocity gradient (LVG) analysis, using spectroscopic data, for each of the species. We have calculated energies of 250 lower rotational levels (up to 98 cm–1) for each species and the Einstein $$A$$ and $$B$$ coefficients for 1231 (ortho) and 1229 (para) radiative transitions between the levels. The collisional rate coefficients, required for the analysis, are calculated with the help of a scaling law. Very exciting results are obtained; we have analyzed 6 potential transitions for each species of CH2(CN)2, which may play important role in the identification of malononitrile in a cosmic object.