A dictionary is a reference book that lists words in alphabetical order, gives their meanings, and provides information about their pronunciation, grammatical forms and functions, etymologies, syntactic peculiarities, variant spellings, and antonyms. This paper analyzes the problems existing in using dictionaries and finds that some dictionaries have problems in themselves and in the users’ misusage of the dictionaries, which devalues the functions of good dictionaries. Therefore, some effective strategies and methods are introduced to use dictionaries in English study including the ability in choosing good dictionaries and interpreting the information given in the entry. A dictionary is a reference book that lists words in alphabetical order, gives their meanings, and provides information about their pronunciation, grammatical forms and functions, etymologies, syntactic peculiarities, variant spellings, and antonyms. This paper analyzes the problems existing in using dictionaries and finds that some dictionaries have problems in themselves and in the users’ misusage of the dictionaries, which devalues ​​the functions of good dictionaries. Therefore, some effective strategies and methods are introduced to use dictionaries in English study including the ability in choosing good dictionaries and interpreting the information given in the entry.