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Following the work of Burgess et al. (1991), the EUV line ratios fran MgVII and SiIX ions have been computed using most appropriate atomic data. The density dependent line ratio R1 = epsilon (2s2p3 1D0-2s(2)2p2 1D)/epsilon(2s2p3 3s0-2s(2)2p2 3P2) and R2 = epsilon(2s2p3 1P0 - -2s(2)2p2 1D)/epsilon(2s2p3 3S0-2s(2)2p2 3P2) for MgVII and SiIX are compared with the earlier results of Mason arid Bhatia (1978) and Keenan et al. (1986). Electron densities derived using observed R1 and R2 ratios from skylab NRL EUV spectra of solar flares and active regions are tabulated along with the values obtained by Keenan et al. (1986).