diff --git a/keras_retinanet/bin/evaluate.py b/keras_retinanet/bin/evaluate.py
index 53695aea9..d2fe09012 100755
--- a/keras_retinanet/bin/evaluate.py
+++ b/keras_retinanet/bin/evaluate.py
@@ -96,7 +96,7 @@ def parse_args(args):
     parser.add_argument('model',              help='Path to RetinaNet model.')
     parser.add_argument('--convert-model',    help='Convert the model to an inference model (ie. the input is a training model).', action='store_true')
     parser.add_argument('--backbone',         help='The backbone of the model.', default='resnet50')
-    parser.add_argument('--gpu',              help='Id of the GPU to use (as reported by nvidia-smi).', type=int)
+    parser.add_argument('--gpu',              help='Id of the GPU to use (as reported by nvidia-smi).')
     parser.add_argument('--score-threshold',  help='Threshold on score to filter detections with (defaults to 0.05).', default=0.05, type=float)
     parser.add_argument('--iou-threshold',    help='IoU Threshold to count for a positive detection (defaults to 0.5).', default=0.5, type=float)
     parser.add_argument('--max-detections',   help='Max Detections per image (defaults to 100).', default=100, type=int)