| Inns | HS |
| 263-9 | 73 | Namibia Under-19s v Canada Under-19s | ICC Cricket Academy Ground No 2, Dubai | 2013/14 |
| 248-6 | 86 | Namibia Under-19s v Scotland Under-19s | Willowmoore Park Main Oval, Benoni | 2023/24 |
| 231-5 | 69 | Namibia Under-19s v Zimbabwe Under-19s | Galle International Stadium, Galle | 1999/00 |
| 226 | 53* | Namibia Under-19s v Canada Under-19s | Colin Maiden Park No 2, Auckland | 2001/02 |
| 225-9 | 59 | Namibia Under-19s v Nepal Under-19s | Khan Shaheb Osman Ali Stadium, Fatullah | 2015/16 |
| 219-8 | 58 | Namibia Under-19s v United States of America Under-19s | Sinhalese Sports Club Ground, Colombo | 2005/06 |
| 201-5 | 62 | Namibia Under-19s v New Zealand Under-19s | Hagley Oval, Christchurch | 2001/02 |
| 196-9 | 44 | Namibia Under-19s v England Under-19s | Queenstown Events Centre, Queenstown | 2017/18 |
| 194-8 | 78 | Namibia Under-19s v Zimbabwe Under-19s | Sheikh Zayed Stadium Nursery 2, Abu Dhabi | 2013/14 |
| 193 | 48 | Namibia Under-19s v Zimbabwe Under-19s | Lincoln No 3, Lincoln | 2001/02 |
| 193 | 38 | Namibia Under-19s v Canada Under-19s | Bert Sutcliffe Oval, Lincoln | 2017/18 |
| 192-9 | 84 | Namibia Under-19s v Afghanistan Under-19s | Sheikh Zayed Stadium Nursery 2, Abu Dhabi | 2013/14 |
| 186-7 | 70 | Namibia Under-19s v Ireland Under-19s | Moors Sports Club Ground, Colombo | 1999/00 |
| 186 | 62 | Namibia Under-19s v Ireland Under-19s | Lincoln No 3, Lincoln | 2017/18 |
| 181 | 40 | Namibia Under-19s v Bangladesh Under-19s | Sheikh Zayed Stadium Nursery 1, Abu Dhabi | 2013/14 |
| 180 | 56 | Namibia Under-19s v Nepal Under-19s | Peter Burge Oval, Brisbane | 2012 |
| 173 | 32 | Namibia Under-19s v Scotland Under-19s | Sheikh Zayed Stadium, Abu Dhabi | 2013/14 |
| 170 | 61 | Namibia Under-19s v India Under-19s | R Premadasa Stadium, Colombo | 2005/06 |
| 166 | 69 | Namibia Under-19s v Kenya Under-19s | Air Force Ground, Katunayake | 1999/00 |
| 166 | 32 | Namibia Under-19s v Zimbabwe Under-19s | WEP Harris Oval, Brisbane | 2012 |
| 163 | 56 | Namibia Under-19s v Australia Under-19s | Penang Sports Club, Penang | 2007/08 |
| 162-1 | 67* | Namibia Under-19s v Scotland Under-19s | Sheikh Kamal International Cricket Stadium, Cox's Bazar | 2015/16 |
| 161-9 | 38 | Namibia Under-19s v England Under-19s | NF Oppenheimer Ground, Randjesfontein | 1997/98 |
| 161 | 65 | Namibia Under-19s v Nepal Under-19s | University Sains Malaysia, Penang | 2007/08 |
| 160 | 48 | Namibia Under-19s v New Zealand Under-19s | LC de Villiers Oval, Pretoria | 1997/98 |
| 160-3 | 55* | Namibia Under-19s v Scotland Under-19s | Colombo Cricket Club Ground, Colombo | 2005/06 |
| 152 | 33 | Namibia Under-19s v India Under-19s | Khan Shaheb Osman Ali Stadium, Fatullah | 2015/16 |
| 151 | 40 | Namibia Under-19s v Bangladesh Under-19s | Peter Burge Oval, Brisbane | 2012 |
| 150 | 37 | Namibia Under-19s v South Africa Under-19s | Peter Burge Oval, Brisbane | 2012 |
| 147-1 | 60* | Namibia Under-19s v Malaysia Under-19s | Johor Cricket Academy Oval, Johor | 2007/08 |
