It's a surprise to me, but I can find only one solid instance of this book being banned anywhere... A surprise given the general moral character described in the book - I found it offensive, and if teens were reading it, I would imagine many a stuck up parent would find it offensive too. But, here is the reference.
This book was banned in South Africa as discussed in the following essay at http://www.the-write-stuff.com.au/archives/vol-1/reviews/good-blonde.html
"ROAD GANG STILL LEADS THE PACK"
Reviewed by Giles Hugo
"WHEN I first encountered Jack Kerouac's writing I was working in a Johannesburg bookshop. Every week we were issued a copy of Jakobsen's List, detailing all the decisions of the South African Publications Control Board (PCB). If a book was banned, you had to return it to the publisher, embargoed books were taken off the shelves pending a decision by the PCB, and a title released from embargo could be put back on sale. Very rarely a book was unbanned.
That was back in 1968, and I didn't hang around in the job long enough to see the works of Jack Kerouac unbanned. But I did manage to acquire as much of the Duluouz saga as I could. As soon as one of his titles came in it was usually listed as embargoed, and I would put one aside for myself. 'On the Road' was already banned, so I had to wait until I got to London later that year to up on the classic that made his reputation. Instead I started with 'Desolation Angels', and I still think it is a fuller, more intriguing work than 'On the Road'. "