The invention discloses a television tuner. The television tuner comprises multiple television signal receiving channels, multiple AV monitoring channels, a single-chip microcomputer and a monitoring unit. The television signal receiving channels receive television signals through antennas. The AV monitoring channels are connected with the television signal receiving channels respectively and used for converting the television signals into monitoring electric signals. The single-chip microcomputer is connected with the AV monitoring channels and used for receiving the monitoring electric signals. The monitoring unit is connected with the single-chip microcomputer through an Ethernet communication module and used for monitoring the monitoring electric signals, and when the monitoring electric signals are abnormal, an alarming device is controlled to give an alarm. Remote monitoring and alarming can be conducted, the working intensity of workers in a transmitting station is greatly relieved, and the broadcasting reliability of the television signals is improved.