As you can probably guess, prepositional pronouns are those that come after prepositions. In a sentence such as "Tengo una sorpresa para ella (I have a surprise for her), para (for) is the preposition and ella (her) is the prepositional pronoun.
Here are the prepositional pronouns of Spanish along with examples of their usage:
- mí (first-person singular, equivalent of "me"): El regalo es para mí. The gift is for me.
- ti (informal second-person singular, equivalent of "you"): El regalo es para ti. The gift is for you.
- usted (formal second-person singular, equivalent of "you"): El regalo es para usted. The gift is for you.
- él (third-person masculine singular, equivalent of "him" or "it"): El regalo es para él. The gift is for him. Miro bajo él. I am looking under it.
- ella (third-person feminine singular, equivalent of "her" or "it"): El regalo es para ella. The gift is for her. Miro bajo ella. I am looking under it.
- nosotros, nosotras (first-person plural, equivalent of "us"): El regalo es para nosotros. The gift is for us.
- vosotros, vosotras (second-person informal plural, equivalent of "you"): El regalo es para vosotros. The gift is for you.
- ustedes (second-person formal plural, equivalent of "you"): El regalo es para ustedes. The gift is for you.
- ellos, ellas (third-person plural, equivalent of "them"): El regalo es para ellos. The gift is for them.
Note on sí: There is also another prepositional object that is occasionally used. Sí is used to mean "himself," "herself," the formal "yourself," the formal "yourselves," or "themselves" as the object of a preposition. For example, él compra el regalo para sí, he is buying the gift for himself. One reason you don't see this usage very often is because the meaning is usually expressed using the reflexive form of the verb: Se compra un regalo, he is buying himself a gift.
Note on "it": Either él or ella can mean "it" as the object of a preposition, although as a subject there is no Spanish word used for "it." The word used depends on the gender of the noun it replaces, with él being used for masculine nouns and ella being used for feminine nouns. ¿Dónde está la mesa? Necesito mirar bajo ella. Where is the table? I need to look under it. ¿Dónde está el carro? Necesito mirar bajo él. Where is the car? I need to look under it.
Similarly, ellos and ellas, when used as a preposition pronoun meaning "them," can be used to represent things as well as people. Use ellos when referring to nouns that are masculine, ellas for feminine nouns.
Contigo and conmigo: Instead of saying con mí and con ti, use conmigo and contigo. Él va conmigo, he is going with me. Ella va contigo, she is going with you. You also should use consigo instead of con sí, although this word isn't very common. Él habla consigo, he talks with himself.
The exceptions: Finally, note that yo and tú are used with the following six prepositions instead of with mí and ti, respectively: excepto (usually translated as "except"), incluso ("including" or "even"), menos ("except"), salvo ("except") and según ("according to"). Also, hasta is used with the subject pronouns when it is used in the same way as incluso. Examples:
- Es la diferencia entre yo y tú. It's the difference between you and me.
- Muchas personas incluso/hasta yo creen en las hadas. Many people including me believe in fairies.
- Todos excepto/menos/salvo tú creen en las hadas. Everybody except you believes in fairies.
- Es la verdad según yo. It's the truth according to me.

