The present invention relates to an N-acrylimino compound of formula (I), wherein X is O or S, in particular O； Het is a 5- or 6-membered carbon- or nitrogen-bonded heterocyclic ring W1-W2-W3-W4 represents a carbon chain group linked to N and C = N, thereby forming a saturated, unsaturated, or partially unsaturated 5- or 6-membered nitrogen-containing heterocycle. (W1, W2, W3 and W4 each independently represent CRvRw), R1, R2 may be hydrogen, halogen, etc., and R3 is a group consisting of hydrogen, halogen, CN, C1-C6-alkyl, etc. R4 is selected from the group consisting of hydrogen, halogen, CN, C1-C10-alkyl, etc., and R5 is hydrogen, CN, C1-C10-alkyl, C2-C10-alkenyl, C3-C8-cyclo Alkyl, S (O) nNR9aR9b, O-NR9aR9b, NR9aR9b, NR9aNR9aR9b, NR9aC (= O) R7a, NR9aC (= S) R7a, NR9aC (= O) NR9aR9b, NR9aC (= S) NR9aR9b, C = , C (= O) NR9aR9b, C (= S) NR9aR9b, C (= O) R7a, C (= S) R7a, Partial Q-Fe (The phenyl ring is optionally substituted with 1, 2, 3, 4 or 5 identical or different substituents R10), and the moiety Q-Het # (Het # is 3-10 membered saturated, Represents a partially saturated or unsaturated aromatic heterocyclic ring). The invention also relates to the use of N-acrylimino heterocyclic compounds, their stereoisomers, their tautomers and their salts for combating invertebrate pests. Furthermore, the present invention also relates to a method for combating invertebrate pests comprising applying such compounds. [Chemical 1]本発明は、式（I)のN-アクリルイミノ化合物に関し、ここで、Xは、O又はS、特にOであり；Hetは、5又は6員の炭素結合又は窒素結合複素環式環であり、W1-W2-W3-W4は、N及びC=Nに連結し、それにより飽和、不飽和、又は部分不飽和の5又は6員の窒素含有複素環を形成している炭素鎖基を表し（W1、W2、W3及びW4は、それぞれ独立にCRvRwを表す）、R1、R2は、水素、ハロゲンなどであってよく、R3は、水素、ハロゲン、CN、C1-C6-アルキルなどからなる群から選択され、R4は、水素、ハロゲン、CN、C1-C10-アルキルなどからなる群から選択され、R5は、水素、CN、C1-C10-アルキル、C2-C10-アルケニル、C3-C8-シクロアルキル、S(O)nNR9aR9b、O-NR9aR9b、NR9aR9b、NR9a NR9aR9b、NR9aC(=O)R7a、NR9aC(=S)R7a、NR9aC(=O)NR9aR9b、NR9aC(=S)NR9aR9b、C(=O)OR8、C(=O)NR9aR9b、C(=S)NR9aR9b、C(=O)R7a、C(=S)R7a、部分Q-フェニル（フェニル環は、1、2、3、4又は5個の同じ又は異なる置換基R10で場合によって置換されている）、及び部分Q-Het#（
