Son returned to his homeland after the Premier League season was suspended in March due to the coronavirus pandemic.
The 27-year-old took the opportunity to complete a three-week period of military training with a Marine Corps unit in Jeju.
Officials told the Yonhap News Agency that Son was awarded the 'Pilsung' prize for being one of the best performers, perhaps unsurprisingly excelling with his shooting skills.
Son is due to return to London next week as clubs await news of when they will be back in action.
South Korea star Son was exempted from the mandatory 21-month military service after leading the national team to a gold medal at the Asian Games in September 2018.
The former Bayer Leverkusen man suffered a broken arm in February but appears ready to fire on all cylinders when Spurs are cleared to return.