Every time I want to POST an array of JSON objects with jQuery to Rails, I have this problem. If I stringify the array I can see that jQuery is doing its work correctly: "shared_items"=>"[{\"entity_id\":\"253\",\"position\":1},{\"entity_id\":\"823\",\"position\":2}]" But if I just send the array it as the data of the AJAX call I get: "shared_items"=>{"0"=>{"entity_id"=>"253", "position"=>"1"}, "1"