there is disclosed an iminothiazoline compound of the formula : ## str1 ## wherein r 1 is halogen , haloalkyl , haloalkoxy or haloalkylthio ; r 2 is lower alkyl , chlorine ; bromine or iodine ; r 3 is carbonyl , carbonyl , carbonyl , carbonyl or sulfonyl , all of which are optionally substituted with at least one substituent selected from halogen , lower alkyl , lower alkoxy , lower cycloalkyl and lower cycloalkoxy ; and r 4 is halogen . also disclosed are a process for producing this compound , a herbicidal composition comprising this compound as an active ingredient , and a method for controlling undesired weeds by use of this compound as a herbicide .