flour has a diphthong
flower has two syllables

The distinction is so slight that in practical terms, they are pronounced the same.  However, with certain dialects, they can sound different.  "Flour" has more of an a sound, and "flower" has more of a "u" sound.  The important thing is that it is by the context in which we discern which word you are using.  For example, "hire" and "higher".

What the pronunciation difference between flour and flower

When I had dialog with my english teacher in last night, she corrected my pronunciation about the word "flower". i was read it like [ˈflauə], the same as the pronunciation about "flower", but my teacher said there were different, the right pronunciation about "flour" is [flaː]. I feel uncertain, can anyone tell me if there's any difference in pronunciation between "flower" and "flour"? They're identical to me, just what i see in the dictionary.

What the pronunciation difference between flour and flower

When I had dialog with my english teacher in last night, she corrected my pronunciation about the word "flower". i was read it like [ˈflauə], the same as the pronunciation about "flower", but my teacher said there were different, the right pronunciation about "flour" is [flaː]. I feel uncertain, can anyone tell me if there's any difference in pronunciation between "flower" and "flour"? They're identical to me, just what i see in the dictionary.

I am only answering your question... I am not making corretions.

The IPA of each word is the same. [ˈflaʊər] is the IPA for both words. They are pronounced the same in English. I am uncertain why your instructor would tell you that there are two different pronunciation, but that is incorrect. Also, the respelling system (American English) spells them the same way as well... [flou-er] In British English they sound the same as well. I hope this helps.

~Samantha  :)

What the pronunciation difference between flour and flower

When I had a dialog with my english teacher in last night, she corrected (my pronunciation about) how I pronounced the word "flower". i was read/pronounced it like [ˈflauə], the same way as (the pronunciation about)the "flower", but my teacher said there they were different, the right pronunciation about of "flour" is [flaː]. I feel uncertain, can anyone tell me if there's any difference in  between "flower" and "flour" pronunciation? They're identical to me, just what i see in the dictionary.

The preposition wich is used with the word pronunciation is of.

And about these two words, they have almost identical pronunciation. 

http://dictionary.cambridge.org/dictionary/british/flower_1?q=flower#

http://dictionary.cambridge.org/dictionary/british/flour_1?q=flour