how to renew passport of minor Hongkong citizen stayed in Ph for 10 years?

If you want to renew HKSAR passport overseas, you download from the website of HK Immigration Department (www.immd.gov.hk) for the form ID843 and also its instruction.
With a complete the form, and all required documents, You can submit the application to the nearest Embassy or Consulate of China. They will send the application to Hong Kong for approval. The ready new passport will be send back to the same Embassy or Consulate of China. The processing time needed is about one month.