Lenell John-Lewis pounced with a late winner to get York's National League campaign back on track and hand Southend a third successive loss at Roots Hall.
John-Lewis followed up an initial effort from Callum Howe to poke home in the 89th minute and snatch the visitors a first win in three against the run of play.
York started well with Dipo Akimyemi denied an early chance and Ben Davies hitting the post after errors in the home defence.
But Southend pressed after the break with York keeper Gus Sykes-Kenworthy pulling off a great stop to deny Adam Crowther, before Crowther missed another good chance in the closing stages.
Match report supplied by PA Media
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