Не особо знаком с jquery, но я сделал так:
jquery:
$( document ).ready(function() {
$('#EditModal').on('show.bs.modal', function (event) {
    var button = $(event.relatedTarget)// Button that triggered the modal
    var url = button.data('ajax_url');
    var id = button.data('id');
    var modal = $(this);
    var item = $("#item-"+id).data();
    modal.find('#form_m').attr('action', url)
    modal.find('.modal-body #item-name').val(item.name)
    modal.find('.modal-body #item-description').val(item.description)
    modal.find('.modal-body #item-price').val(item.price)
    modal.find("select[name='item_type_id']  option[value='"+item.item_type_id+ "']").attr("selected","selected");
    modal.find("select[name='brand_id']  option[value='"+item.brand_id+ "']").attr("selected","selected");
    //$('#ajax_edit_data').on('click', function(){
    //
    //    $.ajax( {
    //        type: 'POST',
    //        url: url,
    //        data: modal.find('#form_m').serialize(),
    //        success: function(data){
    //            alert(data)
    //        }
    //    });
    //
    //})
});
$('#DeleteModal').on('show.bs.modal', function (event) {
    var button = $(event.relatedTarget) // Button that triggered the modal
    var link = button.data('del_url')
    var modal = $(this);
    modal.find('#form_d').attr('action', link)
});
});
модал:
<div class="modal fade" id="EditModal" tabindex="-1" role="dialog" aria-labelledby="Edit">
    <div class="modal-dialog" role="document">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">×</span></button>
                <h4 class="modal-title" id="exampleModalLabel">Edit item</h4>
            </div>
                <div class="modal-body">
                    <form action="replaced_with_js" method="POST" id="form_m">
                        {!!method_field('PUT')!!}
                        {!! csrf_field() !!}
                    <div class="form-group">
                        <label for="recipient-name" class="control-label">Name:</label>
                        <input type="text" class="form-control" id="item-name" name="name">
                    </div>
                    <div class="form-group">
                        <label for="message-text" class="control-label">Description:</label>
                        <textarea class="form-control" id="item-description" rows="10" name="description"></textarea>
                    </div>
                    <div class="form-group">
                        <label for="message-text" class="control-label">Price:</label>
                        <input type="text" class="form-control" id="item-price" name="price">
                    </div>
                    <div class="form-group">
                        <label class="control-label">Item Type:</label>
                        <select class="form-control" name="item_type_id">
                            @foreach($itemTypes as $i)
                                <option value="{{$i['id']}}">{{$i['name']}}</option>
                            @endforeach
                        </select>
                    </div>
                    <label class="control-label">Item Type:</label>
                    <select class="form-control" name="brand_id">
                        @foreach($brands as $b)
                            <option value="{{$b['id']}}">{{$b['name']}}</option>
                        @endforeach
                    </select>
                        </form>
                </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
                <button type="submit" class="btn btn-primary" form="form_m">Approve</button>
            </div>
        </div>
    </div>
</div>
итем:
<table class="table">
                <thead>
                <tr>
                    <th>id</th>
                    <th>name</th>
                    <th>price</th>
                    <th>action</th>
                </tr>
                </thead>
                @foreach($items as $i)
                    <tr id="item-{{$i['id']}}" data-name="{{$i['name']}}"
                        data-description="{{$i['description']}}"
                        data-price="{{$i['price']}}"
                        data-item_type_id="{{$i['item_type_id']}}"
                        data-brand_id="{{$i['brand_id']}}">
                        <td>{{$i['id']}}</td>
                        <td>{{$i['name']}}</td>
                        <td>{{$i['price']}}</td>
                        <td>
                            <button type="button" class="btn btn-primary"
                                    data-toggle="modal" data-target="#EditModal"
                                    data-ajax_url="{{URL::to('/admin')}}/{{$i['id']}}"
                                    data-id="{{$i['id']}}">
                                Edit
                            </button>
                            <button type="button" class="btn btn-danger"
                                    data-toggle="modal" data-target="#DeleteModal"
                                    data-del_url="{{URL::to('/admin')}}/{{$i['id']}}">
                                Delete
                            </button>
                        </td>
                    </tr>
                @endforeach