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Thiophene oligomers (nT) with two to six units in solution are studied under pulse excitation (308 nm,350 fs) in the spectral range 430−830 nm. Transient absorption and induced fluorescence emerge within 1−2 ps. An “instant” absorption (A0), which shows a size dependent spectral structure superimposes the induced fluorescence during the first 500 fs. The fast kinetic processes of different nT are very similar during the first picosecond. They were interpreted as relaxation starting from the highest accessible electronic level down to the lowest excited-state S1 of each oligomer.