Analysis is presented in this paper to fit the theoretical S-wave acceleration spectra conditioned by frequency-independent Q with the observed acceleration spectra. The estimate of error is given in the root-mean-square sense over all the frequencies. The data of two major earthquakes in the Garhwal Himalayas, namely the 1991 Uttarkashi Earthquake and the 1999 Chamoli Earthquake, has been used in the present study to obtain source parameters of these earthquakes and Q value in the source region. Independent estimates of Q at various stations give its average value as 267±87. The stress drop for the Uttarkashi and the Chamoli earthquakes is computed as 77 and 29 bars, respectively, from the near-field acceleration spectra of BHAT and GOPE stations. This agrees with the other observed values of stress drop in the Himalayas.