Quasi-periodical oscillations of positions of coronal loops were observed in the extreme-ultraviolet band (171A, FeIX) with the imaging telescope onboard the TRACE spacecraft. Oscillating transversal displacements (swinging) of a long (∼130 Mm) thin (diameter ∼2 Mm) bright loop, were detected. The oscillations were excited by a flare (14th July 1998 at about 12:55 UT) at distance of about 60 Mm from the loop. The frequency of the oscillations was about 4 mHz (the period about 265 s) and was determined by the wavelet analysis. Neighboring perpendicular slits show synphase temporal behavior, suggesting that the oscillations are produced by akink global fast magnetoacoustic modeof the loop. With this interpretation, we determine the kink speed in the loop as 1040 km/s, which gives the Alfve´n speed of about770±40&hthinsp;km/s.The detection and analysis of post-flare oscillations of coronal loops provides us with an efficient tool for indirect determination of coronal parameters, e.g. the magnetic field found to be of about 20 G. ©2000 American Institute of Physics.