  We numerically investigate dynamical and chemical properties of star clusters
(open and globular clusters, and ``super star clusters'', SSC) formed in
interacting/merging galaxies. The investigation is two-fold: (1) large-scale
(100pc-100kpc) SPH simulations on density and temperature evolution of gas in
interacting/merging galaxies and (2) small-scale ones on the effects of high
gas pressure of ISM on the evolution of molecular clouds. We find that the
pressure of ISM in merging galaxies can become higher than the internal
pressure of GMCs ($\sim$ $10^5$ $\rm k_{\rm B}$ K $\rm cm^{-3}$), in
particular, in the tidal tails or the central regions of mergers. We also find
that GMCs can collapse to form super star clusters within an order of $10^7$ yr
owing to the strong compression by the high presser ISM in mergers.
