With key fishing quota talks due to take place next week in Brussels, Mr Lochhead said ensuring the Scottish fleet's days at sea remained the same would be a key objective.
He also told MSPs he would be pressing the UK Government to work towards getting a "moderate increase" in the amount of cod Scottish fishermen are allowed to catch.
"We always seem to face stiff challenges and difficult decisions at the end of year fisheries negotiations," Mr Lochhead said.
"I will ensure Scotland's priorities are uppermost in the minds of UK ministers and we will do our utmost to fight for Scotland's interest right across the board."
UK Government ministers will take part in the talks, as it is the UK that is a member of the European Union (EU), but Mr Lochhead and Scottish Government representatives will also play a part in the crucial discussions.
The Environment Secretary explained next week's talks would only decide the quotas for EU waters.
Quotas for North Sea stocks of fish such as cod, haddock and whiting - which are shared between the EU and Norway - will be determined at talks next year.
"So it is all still there to play for," Mr Lochhead said.
He conceded the talks "would be challenging" as the scientific advice suggested catch levels should be decreased to help preserve fish stocks.
But he added: "I am determined, within those circumstances, to negotiate the best possible deal for Scotland's fishermen."