The Liga new boys have upped the Portuguese contingent in their squad to seven after securing the services of the young pair for the rest of the season
The Portuguese duo will join the newly-promoted La Liga side on season-long loans, before returning to the Estadio da Luz at the end of the campaign.
They will undergo a medical at Deportivo on Tuesday morning before being officially unveiled at the Riazor at the end of the day.
Oliveira, who is widely regarded as one of the brightest prospects his country have produced in recent years, made only nine competitive starts for Benfica in 2011-12.
However, he caught the eye of Portugal coach Paulo Bento and was included in the Seleccao's 23-man squad for Euro 2012, earning four caps in Poland and Ukraine.
Roderick, an Under-20 international for Portugal, spent last season on loan at side Servette, during which he featured 24 times for the Swiss Super League side.