非永久性居民有案底还可以申请永久性居民吗?

須視乎不同情況而定，若果是持單程證到港的話，不受影響，因大陸戶籍已經註銷，不能回頭。

It depends.

Immigration Department does not require the proof of good character (no criminal record) for the basis of permanent residence.

However, if you have a criminal record and have been served time in a prison, your time spent in the prison will not count toward the 7-year requirement.

For example, if a new immigrant has served 1 year in prison before reaching the 7-year, he/she will need to reside in Hong Kong for a additional year to make up the time.