Adam Kaminski and Justyna Swiatek both aged 26 and of Union Court, Boston, are both accused of murdering Marcin Stolarek.
The body of Mr Stolarek, who was 46 and originally from Poland, was found in the South Forty Foot Drain on Chain Bridge Road, Boston, on Sunday 12 January.
Adam Maksajda, 33, of no fixed address, also appeared in the dock accused of perverting the course of justice in relation to the murder.
All three had appeared before Lincoln Magistrates earlier today.
Judge John Pini QC adjourned the case for a plea and trial.preparation hearing on 21 February. A provisional trial date was set for 29 June.
There were no applications for bail and the three defendants were each remanded in custody.