The 40-year-old has been in impressive form with the bat, scoring centuries in both innings in the second Test in Abu Dhabi as Pakistan completed a series whitewash over Australia and also making 102 not out in the victory over New Zealand in the first Test.
Pakistan lead the three-match series against the Black Caps 1-0 ahead of the final Test, which starts on Wednesday, and with no more five-day internationals scheduled before next year's ICC World Cup, Misbah is unsure when will be the final time he features in the longest form of the game.
When asked if this will be his final Test, Misbah said: "That's a difficult question. Obviously, I have been the one who has really been thinking about that for days and days. Let's see.
"Obviously I've just been planning but at the moment I haven't announced anything because I just want to focus on whatever comes in and just want to play as accordingly as the career is coming.
"But obviously I've been thinking about the World Cup and what my plans are after that."
Pakistan pulled off a remarkable run chase to beat Sri Lanka by five wickets in their last Test in Sharjah, with Azhar Ali making a century as they racked up 302-5 on the final day.
Misbah also played his part with an unbeaten 68 and the veteran right-hander is hoping the Sharjah Cricket Stadium proves to be a happy hunting ground once again.
He said: "At the moment, looking at the pitch, it looks like hard work for the bowlers.
"Obviously, familiar conditions and our team did really well, especially the last Test match we played here, that was a historic one. So we've really been looking forward to just replicating that sort of performance and try to win the Test match."
Mohammad Hafeez has linked up with the squad after his bowling action was tested in England last week, but the all-rounder is set to undergo a fitness test due to a hamstring injury.
"I think he was just having his fitness test and met the physio after that. Let's see how his condition is, especially his hamstring because he just returned from England so we'll see. If he's fit and he's feeling well then we'll definitely just consider him." said Misbah.