Here is a page of kid's haiku for halloween. They each have 17 syllables. http://longwood.cs.ucf.edu/~MidLink/haikus.html
haiku is a Japanese form of poery that contains only 17 syllables.
"Seventeen Syllables in a Haiku Poem". 17 = Syllables in a Haiku Poem
Haiku poems traditionally consist of three, unrhymed lines. The first line contains five syllables. The second contains seven syllables. The third contains five syllables. The total number of syllables is seventeen.
Haiku
A popular example of a poem with 8 syllables in each line is a "haiku." A haiku consists of three lines with a 5-7-5 syllable structure, totaling 17 syllables in all.
17 syllables in a haiku poem
haiku
A traditional haiku in Japanese consists of 17 on, which are phonetic sound units, not syllables. In English haiku, the 17 syllable rule is a convention to help capture the brevity and essence of the form while reflecting the structure of a traditional haiku.
A haiku is a three line poem that follows this pattern: the first line is five syllables, the second line is seven syllables, and the third line is five syllables, for a total of seventeen syllables. "Each Haiku must contain a kigo, a season word, which indicate in which season the Haiku is set. For example, cherry blossoms indicate spring, snow indicate winter, and mosquitoes indicate summer, but the season word isn't always that obvious."
"Haiku"
A haiku is a short Japanese poem with 17 morae, similar to syllables, in lines of 5, 7, and 5.
A traditional Japanese haiku has three lines. The first and third lines have five syllables, while the second line has seven syllables. They do not usually rhyme but on can. As the short answer to your question there are seventeen syllables.