The central region of our Galaxy contains a huge amount of molecular gas. This region is often referred to as the "central molecular zone (CMZ)". High-velocity compact clouds (HVCC) are a peculiar population of molecular clouds found in the CMZ of our Galaxy. HVCCs are characterized by their compact sizes and large velocity widths. In this seminar, I introduce some HVCCs which have been studied so far. Some of them comtain small expanding arcs and shells. They are assumed to be formed by a series of supernova explosions. This means that they should be associated with compact, young and massive stellar clusters. We have also found another type of HVCC, which is more compact than any previously known HVCCs. The recent ALMA observations toward this HVCC revealed orbital motions around an invisible massive object, which is probably an intermediate-mass black hole.