试试这个

_textView = [[UITextView alloc] initWithFrame:rect];

NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
paragraphStyle.lineSpacing = 5;

NSDictionary *attributes = @{
         NSFontAttributeName:[UIFont systemFontOfSize:14],
         NSParagraphStyleAttributeName:paragraphStyle
         };
_textView.attributedText = [[NSAttributedString alloc] initWithString:@"111" attributes:attributes];