Novel 2-(2',2'-dihalovinyl)-cyclobutan-1-ones and 2-(2',240 ,2'-trihaloethyl)-cyclobutan-1-ones of the formula ##STR1## are disclosed, wherein R.sub.1 represents --CH.dbd.CX.sub.2 or --CH.sub.2 --CX.sub.3, and X in each case represents chlorine or bromine, one of R.sub.2 and R.sub.3 represents methyl and the other represents hydrogen or methyl, or R.sub.2 and R.sub.3 together represent an alkylene group having 2 to 4 carbon atoms. The invention relates also to the production and the use of the said cyclobutanones.