The u.v.-visible electronic spectra of 4-arylidene-1-(2, 4-dinitrophenyl)-3-methyl-2-pyrazolin-5-ones (1a-f) have been studied. The different bands observed have been assigned to the proper electronic transition. Solvatochromic behaviour of these compounds is investigated by studying their visible spectra in organic solvents of different polarity. The longer wavelength band displayed by the hydroxy derivatives is assigned to an intermolecular CT transition. The H-bonding solvated complexes formed between ethanol or DMF and p-hydroxy substituted derivative are investigated. Transition moment (CT), G and Kf values of these complexes have been determined.