<P> While the show initially enjoyed high ratings , the average rating of the show at the end of its first season dropped to 52nd out of 94 programs . Unhappy with the show 's ratings , NBC threatened to cancel the show during its second season . The show 's fan base , led by Bjo Trimble , conducted an unprecedented letter - writing campaign , petitioning the network to keep the show on the air . NBC renewed the show , but moved it from primetime to the `` Friday night death slot '' , and substantially reduced its budget . In protest Roddenberry resigned as producer and reduced his direct involvement in Star Trek , which led to Fred Freiberger becoming producer for the show 's third and final season . Despite another letter - writing campaign , NBC cancelled the series after three seasons and 79 episodes . </P>
<P> While the show initially enjoyed high ratings , the average rating of the show at the end of its first season dropped to 52nd out of 94 programs . Unhappy with the show 's ratings , NBC threatened to cancel the show during its second season . The show 's fan base , led by Bjo Trimble , conducted an unprecedented letter - writing campaign , petitioning the network to keep the show on the air . NBC renewed the show , but moved it from primetime to the `` Friday night death slot '' , and substantially reduced its budget . In protest Roddenberry resigned as producer and reduced his direct involvement in Star Trek , which led to Fred Freiberger becoming producer for the show 's third and final season . Despite another letter - writing campaign , NBC cancelled the series after three seasons and 79 episodes . </P>
how many episodes of star trek in total
how many episodes of star trek in total
79
79