The reigning champions were made to work hard for their 2-0 victory at the Parc des Princes, with Thiago Silva and Edinson Cavani getting on the scoresheet.
The win was a must given Ligue 1 leaders Nice were also victorious against Guingamp on Wednesday, and PSG's triumph keeps them one point behind the early pace setters.
Emery believes the tricky nature of the win over mid-table Angers shows how difficult Ligue 1 has become and he was proud of the way his team kept their focus.
"It was an important game to win all the three points for the classification in the table," said Emery. "We played against a tough team, who were very compact defensively, but we did a solid game, playing seriously.
"Ligue 1 is a competitive league with PSG and other good teams, like Lyon, Monaco and Saint Etienne, so the championship is very strong today.
"I think first of our own way and if we do our job, then it pays.''