The invention discloses a substituted
pyridine propionic
acid derivative and application thereof, and belongs to the field of chemical medicines. According to the
pyridine propionic acid compound shown in the general formula (I) or the pharmaceutically acceptable salt of the
pyridine propionic acid compound, in the compound, an A ring, a B ring and a C ring are independently selected from X1, X2, X3 and X4 are independently selected from N and CR, and at least one of X1, X2, X3 and X4 in the A ring is N. The compound disclosed by the invention has an excellent Lp (a) inhibiting effect and can be used as a
medicine for reducing the Lp (a) level of
plasma.