It is only required your valid passport and do not require visa the citizens of the following countries:

AMERICA:
All the citizens of countries of America. Except Cuba.

EUROPE:
All the citizens of countries of the European Union

ASIA:
South Korea
Philippines
Hong Kong
Indonesia
Malaysia
Singapore
Thailand
Taiwan (Taipei)

AFRICA:
South Africa

OCEANIA:
Australia

The citizens of other countries will request Tourist's Visa in the Consulate of Peru in their respective country.
It' possible to get up to 183 days on a tourist visa. But be sure to ask for all 183 days otherwise they might give you just 90 days.
More info: www.digemin.gob.pe

Onward Ticket

Depending on the country you leave from or the airlines you fly on, you might be asked to buy an onward ticket in case you don't have one.
Flying to Chile or Ecuador is cheap, then just refund it when you arrive. In case you are forced to buy a return ticket by the airlines, then simply refund it when you arrive in Peru.

Renewing and Extending Tourist Visas

simply ask for 180 days when you enter Peru or simply border hop and you will be given up to 180 days upon re-entry.

Expired Visa

You'll have to pay a dollar a day if you overstay your visa. The fee is payable at the airport or border crossing.
If you lose your TAM ( tarjeta de migracion andina ), the little white paper you receive when entering to Peru, you will have to get a new one before you leave. The process is kind of easy. Just look for the nearest immigration office with the following documents. The whole process can take between one and three days.

Requirements for the TAM

- Form F002
- Payment 8.17 soles at the Banco de la Nacion
- Original passport and copy of the Peru stamp.