Haslam slipped to 26 points behind Rea in the WSBK standings after finishing off the podium for the first time this season at Aragon after three rounds.
The Red Devils Aprilia rider likes the Assen track and believes that it suits his bike.
"Assen is a track that I like and I think it will suit the characteristics of the RSV4 RF well," said Haslam.
"The experience gained at Aragon will also be fundamental Session after session we are learning how the new bike reacts to our changes and figuring out how to adapt the settings to various conditions," he added.
Team-mate Jordi Torres is hoping to get a first podium finish this weekend after narrowly missing out at Aragon.
"We did a great job at Aragon. The track is long and hard and I learned a lot.
"Now we are off to Assen, a completely different circuit but one that suits my riding style well. I need to continue learning the secrets of this bike and this category.
"We are very close to the faster riders in the championship but I need to manage to keep up with them all the way to the end of the race," he added.