Essien missed the first half of last season after picking up a cruciate ligament injury in the first week of training last July.
In 2010, the box-to-box midfielder suffered a serious knee injury at the Africa Cup of Nations in Angola.
The 29-year-old returned in January but fell down the pecking order in midfield.
He was an unused substitute in the final of the UEFA Champions League which Chelsea won on penalties against Bayern Munich.
Essien is confident of reclaiming his position in the Chelsea set-up.
“It is hard during the season if you miss pre-season,” he told Chelsea’s official website.
“And so it is good to start and hopefully finish the whole pre-season. So I am looking forward to that and we will see what happens.
“So far so good and I am looking forward to the season.”
Essien, if fully fit, will be key for Chelsea manager Roberto Di Matteo who is seeking to impressive after being handed the job a permanent basis.
Di Matteo led Chelsea to their first ever Champions League trophy in May at the Allianz Arena in Munich.