No. It is a language a bit more complex than English. There are, however many regional accents and pronunciations that sometimes are a bit difficult to understand and which could be called dialects.
For instance, in English you can find the American "Color" and the British "Colour", and in the Mexican Spanish you can find the same kind of differences in contrast to the Spaniard or "Standard" Spanish:
Standard Spanish: niño (Boy)
Mexican Spanish: chico, chiquillo, chamaco, chilpayate, escuincle.