The Lions had a poor start to the season but had improved recently, recording two consecutive victories before Reading brought their mini-revial to a halt.
The win took Reading up to seventh in the league, albeit for just a few hours. Pardew admitted he thinks his side are capable of pushing for a place in the top six.
Speaking after the game Pards told readingfc.co.uk: "At the start of the season, if someone had offered me twenty-six points at this stage, I'd have gladly taken it.
"We're in a good position and if the belief stays as it is, we can threaten the top six places.
"It was a big game and 2-0 was a great result for us. Millwall are a very good team, and Mark McGhee's got them going recently - I think they'll finish in the top eight. If we play like that we won't be far away either."
Despite the conclusive scoreline it wasn't plain sailing all the way as Pards acknowledged.
"Millwall had a real go at us, and there were a couple of spells where we had to defend with our lives.
"The way we play means we don't create many chances, but we create good ones. Perhaps we should have taken one or two of them. But, it would have been boring if we'd scored the second goal earlier, we wanted to keep it tense!"
Alan Pardew picked Nathan Tyson ahead of veteran John Salako. The Royals boss admitted his young winger could have done better.
"Millwall's right-back was probably the best player to play against Nathan Tyson, because he's very quick which eliminated Tys a bit.
"To be honest he looked a bit nervous and he's better than what he showed today. He certainly gave a good account of himself and cen be proud of his effort.
"I brought John on as he works the area in front of the full-back better, and he was excellent when he came on. I just felt he needed a rest, and he looked nice and fresh when he came on."