【20以内加减法口诀表】在小学数学学习中，20以内的加减法是基础中的基础。掌握好这一部分的内容，不仅有助于提升计算速度，还能为后续的数学学习打下坚实的基础。为了帮助孩子们更好地记忆和运用这些基本运算规则，下面整理了一份清晰、实用的“20以内加减法口诀表”，便于复习与练习。
一、加法口诀表（1~19）
| 加数 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 |
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |
| 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 |
| 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 |
| 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
| 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 |
| 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 |
| 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 |
二、减法口诀表（2~20）
| 被减数 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - | - |
| 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - | - |
| 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - | - |
| 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - | - |
| 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - | - |
| 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - | - |
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - | - |
| 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - | - |
| 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - | - |
| 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - | - |
| 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - | - |
| 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | - |
三、总结
通过以上表格，我们可以清晰地看到20以内所有可能的加法和减法组合结果。对于小学生来说，建议每天进行一定量的练习，比如随机抽取几组数字进行口算训练，逐步提高准确率和速度。
同时，也可以结合实物操作（如小棒、珠子）或游戏化的方式进行学习，增强趣味性，让孩子们在轻松愉快的氛围中掌握知识点。
掌握好20以内的加减法，是迈向更高年级数学学习的重要一步，希望这份口诀表能对大家有所帮助。
