A power converter comprising: a coolant path structure, a capacitor having a DC terminal (56, 57), a power semiconductor circuit having a DC terminal (26, 33), an AC terminal, and a power semiconductor chip for converting a direct current supplied from said DC terminal (26, 33) to an alternating current by an operation of said power semiconductor chip and outputting it from said DC terminal (26, 33), and a first connecting wire for connecting electrically said DC terminal (56, 57) of said capacitor to said DC terminal (26, 33) of said power semiconductor circuit, wherein: DC power supplied to said housing is supplied to said DC terminal (56, 57) of said capacitor and said DC terminal (26, 33) of said power semiconductor circuit and is converted to AC power by said operation of said semiconductor chip, and said AC power is outputted from said AC terminal of said power semiconductor circuit, characterized by a housing, wherein the coolant path structure is installed in said housing for forming a coolant path for letting a coolant pass, the capacitor is arranged on one side of said coolant path structure in said housing, the power semiconductor circuit is arranged on the other side of said coolant path structure in said housing, the first connecting wire has a laminated structure with a positive bus bar and a negative bus bar being laminated with an insulator therebetween, and the first connecting wire connects the DC terminal (56, 57) of said capacitor and said DC terminal (26, 33) of said power semiconductor circuit with the structure penetrating a hole (1112, 1212) formed in said coolant path structure. a coolant path structure, a capacitor having a DC terminal (56, 57), a power semiconductor circuit having a DC terminal (26, 33), an AC terminal, and a power semiconductor chip for converting a direct current supplied from said DC terminal (26, 33) to an alternating current by an operation of said power semiconductor chip and outputting it from said DC terminal (26, 33), and a first connecting wire for connecting electrically said DC terminal (56, 57) of said capacitor to said DC terminal (26, 33) of said power semiconductor circuit, wherein: DC power supplied to said housing is supplied to said DC terminal (56, 57) of said capacitor and said DC terminal (26, 33) of said power semiconductor circuit and is converted to AC power by said operation of said semiconductor chip, and said AC power is outputted from said AC terminal of said power semiconductor circuit, characterized by a housing, wherein the coolant path structure is installed in said housing for forming a coolant path for letting a coolant pass, the capacitor is arranged on one side of said coolant path structure in said housing, the power semiconductor circuit is arranged on the other side of said coolant path structure in said housing, the first connecting wire has a laminated structure with a positive bus bar and a negative bus bar being laminated with an insulator therebetween, and the first connecting wire connects the DC terminal (56, 57) of said capacitor and said DC terminal (26, 33) of said power semiconductor circuit with the structure penetrating a hole (1112, 1212) formed in said coolant path structure. DC power supplied to said housing is supplied to said DC terminal (56, 57) of said capacitor and said DC terminal (26, 33) of said power semiconductor circuit and is converted to AC power by said operation of said semiconductor chip, and said AC power is outputted from said AC terminal of said power semiconductor circuit, characterized by a housing, wherein the coolant path structure is installed in said housing for forming a coolant path for letting a coolant pass, the capacitor is arranged on one side of said coolant path structure in said housing, the power semiconductor circuit is arranged on the other side of said coolant path structure in said housing, the first connecting wire has a laminated structure with a positive bus bar and a negative bus bar being laminated with an insulator therebetween, and the first connecting wire connects the DC terminal (56, 57) of said capacitor and said DC terminal (26, 33) of said power semiconductor circuit with the structure penetrating a hole (1112, 1212) formed in said coolant path structure.