| Inns | HS |
| 340-5 | 91 | Australia Under-19s v Ireland Under-19s | MA Aziz Stadium, Chittagong | 2003/04 |
| 319-8 | 66 | Australia Under-19s v West Indies Under-19s | Willowmoore Park Main Oval, Benoni | 2019/20 |
| 317-8 | 81 | Australia Under-19s v India Under-19s | Indian Petrochemicals Corporation Limited Sports Complex Ground, Vadodara | 1993/94 |
| 310-9 | 92 | Australia Under-19s v Pakistan Under-19s | Roy Henzell Oval, Caloundra | 2006/07 |
| 296-7 | 89 | Australia Under-19s v Zimbabwe Under-19s | De Beers Diamond Oval, Kimberley | 2023/24 |
| 295 | 45 | Australia Under-19s v Pakistan Under-19s | Mirpur Cricket Stadium, Mirpur | 2007/08 |
| 289-6 | 62 | Australia Under-19s v Pakistan Under-19s | Albert Ground, Melbourne | 1997/98 |
| 288-6 | 72* | Australia Under-19s v Pakistan Under-19s | Deakin Reserve, Shepparton | 1997/98 |
| 285-9 | 76 | Australia Under-19s v New Zealand Under-19s | Endeavour Park, Townsville | 2011/12 |
| 283-8 | 68 | Australia Under-19s v India Under-19s | Municipal Stadium, Rajkot | 1993/94 |
| 281-5 | 69* | Australia Under-19s v England Under-19s | Hagley Oval, Christchurch | 2001/02 |
| 276-7 | 70 | Australia Under-19s v India Under-19s | Western Australia Cricket Association Ground, Perth | 2008/09 |
| 276-7 | 96 | Australia Under-19s v South Africa Under-19s | Queenstown Events Centre, Queenstown | 2009/10 |
| 276-7 | 71 | Australia Under-19s v Pakistan Under-19s | Sir Vivian Richards Stadium, North Sound | 2021/22 |
| 274-9 | 74 | Australia Under-19s v Pakistan Under-19s | Roy Henzell Oval, Caloundra | 2006/07 |
| 274-5 | 88 | Australia Under-19s v Ireland Under-19s | Queenstown Events Centre, Queenstown | 2009/10 |
| 269-7 | 58 | Australia Under-19s v New Zealand Under-19s | Peter Burge Oval, Brisbane | 2019 |
| 268-8 | 58 | Australia Under-19s v New Zealand Under-19s | Lancaster Park, Christchurch | 1992/93 |
| 263-6 | 99 | Australia Under-19s v India Under-19s | Tony Ireland Stadium, Townsville | 2011/12 |
| 262 | 73 | Australia Under-19s v United States of America Under-19s | Queenstown Events Centre, Queenstown | 2009/10 |
| 260-8 | 76 | Australia Under-19s v England Under-19s | Sydney Cricket Ground, Sydney | 2002/03 |
| 254 | 67 | Australia Young Cricketers v New Zealand Young Cricketers | Wentworth Oval, Wentworth | 1987/88 |
| 253-8 | 71 | Australia Under-19s v Pakistan Under-19s | Kimberley Country Club, Kimberley | 1997/98 |
| 253-7 | 47* | Australia Under-19s v England Under-19s | Melbourne Cricket Ground, Melbourne | 2002/03 |
| 253-8 | 65 | Australia Under-19s v England Under-19s | De Beers Diamond Oval, Kimberley | 2019/20 |
| 253-7 | 55 | Australia Under-19s v India Under-19s | Willowmoore Park Main Oval, Benoni | 2023/24 |
| 252-8 | 84 | Australia Under-19s v West Indies Under-19s | Bert Sutcliffe Oval, Lincoln | 2001/02 |
| 251 | 77 | Australia Under-19s v West Indies Under-19s | Sinhalese Sports Club Ground, Colombo | 2005/06 |
| 251-7 | 95 | Australia Under-19s v Sri Lanka Under-19s | Kingston Twin Ovals, Hobart | 2016/17 |
| 251 | 77 | Australia Under-19s v England Under-19s | The 1st Central County Ground, Hove | 2023 |
| 250 | 85 | Australia Under-19s v England Under-19s | County Ground, Hove | 1999 |
