With AFNetworking
NSString *imageUrl = [NSString stringWithFormat:@"http://graph.facebook.com/%@/picture?type=square", @"100003703755434"];
[self.imageView setImageWithURL:[NSURL URLWithString:imageUrl] placeholderImage:[UIImage imageNamed:@"profile.jpg"]];

Image load Sync
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://graph.facebook.com/%@/picture?type=square", @"100003703755434"]];
UIImage *image = [UIImage imageWithData: [NSData dataWithContentsOfURL:url]];
[self.imageView setImage:image];