The present invention provides an agricultural and horticultural fungicidal composition comprising at least one compound (A) which is selected from a nitrogenated heterocyclic compound having a specific structure including a compound represented by formula (1) and a salt of the nitrogenated heterocyclic compound and at least one compound (B) which is selected from a specific agrichemically active compound group. [In formula (1), X's independently represent a halogeno group or a C1-6 alkyl group； n is the number of X's and represents an integer of 0-6； X' represents a halogeno group； and R
