Preheat oven to 350 degrees F (175 degrees C). Grease cookie sheets.
In a large bowl, cream together the butter, white sugar and brown sugar until light and fluffy. Beat in the egg and vanilla. Combine the flour, baking soda, salt and cinnamon; stir into the creamed mixture.
Stir in the oats and chocolate chips.
Drop by rounded tablespoonfuls onto prepared cookie sheets.
Bake for 10 to 12 minutes in preheated oven. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.