Foreigners staying in a hotel, guesthouse, school or other
commercial, non-profit, government or other facilities after
arriving in Beijing need to produce a valid a passport or residence
certificate and fill out a Temporary Lodging Registration Form.
For a foreigner staying at the residence of his relatives or
friends after arriving in Beijing, the host or the foreigner shall
register at the local police station with the host's residence
card, the foreigner' valid passport and other valid identification
documents and fill out a Temporary Lodging Registration Form within
24 hours (72 hours in rural areas) after his arrival.
If a foreigner with a residence permit leaves his residence and
lives temporarily in another place, he needs to fill out a
Temporary Lodging Registration Form at the places of his temporary
stay.
If a foreigner travels an area that is not opened to foreigners,
he must produce his valid passport or residence permit and fill out
a Temporary Lodging Registration Form as well as a travel
permit.
If a foreigner stays in a foreign institution in China or
another foreigner's residence in Beijing, the host or the foreigner
must register at the local public security organ with his passport
or residence documents and fill out a Temporary Lodging
Registration Form within 24 hours of his arrival.
(english.gov.cn)